diff --git a/.env.example b/.env.example
index d6e1c8e..74948b9 100644
--- a/.env.example
+++ b/.env.example
@@ -1,4 +1,3 @@
-```dotenv
 PORT=
 NODE_ENV=
 
@@ -16,4 +15,7 @@ DB_USER=
 DB_PASS=
 DB_NAME=
 DB_DIALECT=
-```
\ No newline at end of file
+
+# Router Configuration
+ROUTER_CALLBACK_TOKEN=
+PROJECT_ID=
\ No newline at end of file
diff --git a/app/modules/bank-transfer/services/bank-transfer.service.js b/app/modules/bank-transfer/services/bank-transfer.service.js
index 5cc5915..f84fe19 100644
--- a/app/modules/bank-transfer/services/bank-transfer.service.js
+++ b/app/modules/bank-transfer/services/bank-transfer.service.js
@@ -16,10 +16,13 @@ class BankTransferService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             payment_type: "bank_transfer",
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             bank_transfer: {
diff --git a/app/modules/credit-card/services/credit-card.service.js b/app/modules/credit-card/services/credit-card.service.js
index 05b82ac..8a5d0c9 100644
--- a/app/modules/credit-card/services/credit-card.service.js
+++ b/app/modules/credit-card/services/credit-card.service.js
@@ -16,10 +16,13 @@ class CreditCardService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             payment_type: "credit_card",
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             credit_card: {
diff --git a/app/modules/cstore/services/cstore.service.js b/app/modules/cstore/services/cstore.service.js
index f304e2d..36df9b0 100644
--- a/app/modules/cstore/services/cstore.service.js
+++ b/app/modules/cstore/services/cstore.service.js
@@ -16,10 +16,13 @@ class CStoreService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             payment_type: store,
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             customer_details: customer_details,
diff --git a/app/modules/e-wallet/services/e-wallet.service.js b/app/modules/e-wallet/services/e-wallet.service.js
index cd966a0..2b99a18 100644
--- a/app/modules/e-wallet/services/e-wallet.service.js
+++ b/app/modules/e-wallet/services/e-wallet.service.js
@@ -16,10 +16,13 @@ class EWalletService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             payment_type: type,
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             customer_details: customer_details,
diff --git a/app/modules/notification/controllers/notification.controller.js b/app/modules/notification/controllers/notification.controller.js
index ed77eaf..20dafb4 100644
--- a/app/modules/notification/controllers/notification.controller.js
+++ b/app/modules/notification/controllers/notification.controller.js
@@ -6,6 +6,11 @@ class NotificationController {
         const payload = req.body;
 
         try {
+            const callbackToken = req.headers['x-callback-token'];
+            if (callbackToken !== process.env.ROUTER_CALLBACK_TOKEN) {
+                return responseHelper.error(res, "Unauthorized token router gateway", 401);
+            }
+
             const isValid = notificationService.verifySignature(payload);
             if (!isValid) {
                 return responseHelper.error(res, "Invalid Signature Key", 403);
diff --git a/app/modules/paylater/services/paylater.service.js b/app/modules/paylater/services/paylater.service.js
index 499e968..9b5eaa4 100644
--- a/app/modules/paylater/services/paylater.service.js
+++ b/app/modules/paylater/services/paylater.service.js
@@ -16,10 +16,13 @@ class PayLaterService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             payment_type: type,
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             customer_details: customer_details,
diff --git a/app/modules/snap/services/snap.service.js b/app/modules/snap/services/snap.service.js
index 215dd37..1a91194 100644
--- a/app/modules/snap/services/snap.service.js
+++ b/app/modules/snap/services/snap.service.js
@@ -16,9 +16,12 @@ class SnapService {
             payload.amount = amount;
         }
 
+        const projectId = process.env.PROJECT_ID;
+        const midtransOrderId = projectId ? `${external_id}-${projectId}` : external_id;
+
         const parameter = {
             transaction_details: {
-                order_id: external_id,
+                order_id: midtransOrderId,
                 gross_amount: amount
             },
             customer_details: customer_details,
diff --git a/tests/unit/bank-transfer.service.test.js b/tests/unit/bank-transfer.service.test.js
index 4e4d656..0378e37 100644
--- a/tests/unit/bank-transfer.service.test.js
+++ b/tests/unit/bank-transfer.service.test.js
@@ -21,13 +21,18 @@ describe('BankTransferService', () => {
         jest.clearAllMocks();
         process.env.MIDTRANS_EXPIRY_DURATION = '1';
         process.env.MIDTRANS_EXPIRY_UNIT = 'hour';
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create a bank transfer transaction (BCA) successfully', async () => {
         const payload = { order_id: 'u-123', external_id: 'INV-001', amount: 10000 };
         mockCharge.mockResolvedValue({ status_code: '201' });
         const result = await bankTransferService.createTransaction(payload, 'bca');
-        expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({ payment_type: 'bank_transfer' }));
+        expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-001-CBT'
+            })
+        }));
         expect(result.status_code).toBe('201');
     });
 
diff --git a/tests/unit/credit-card.service.test.js b/tests/unit/credit-card.service.test.js
index 922eb9c..b8443c8 100644
--- a/tests/unit/credit-card.service.test.js
+++ b/tests/unit/credit-card.service.test.js
@@ -18,13 +18,18 @@ const creditCardService = require('../../app/modules/credit-card/services/credit
 describe('CreditCardService', () => {
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create a credit card transaction successfully', async () => {
         const payload = { order_id: 'u-cc', external_id: 'INV-CC-001', amount: 500000, credit_card_token: 't-123' };
         mockCharge.mockResolvedValue({ status_code: '201', transaction_status: 'capture' });
         const result = await creditCardService.createTransaction(payload);
-        expect(mockCharge).toHaveBeenCalled();
+        expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-CC-001-CBT'
+            })
+        }));
         expect(result.status_code).toBe('201');
     });
 
diff --git a/tests/unit/cstore.service.test.js b/tests/unit/cstore.service.test.js
index d19e0a5..5166935 100644
--- a/tests/unit/cstore.service.test.js
+++ b/tests/unit/cstore.service.test.js
@@ -17,13 +17,18 @@ const cstoreService = require('../../app/modules/cstore/services/cstore.service'
 describe('CStoreService', () => {
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create an indomaret transaction successfully', async () => {
         const payload = { order_id: 'u-123', external_id: 'INV-I-001', amount: 50000 };
         mockCharge.mockResolvedValue({ status_code: '201' });
         const result = await cstoreService.createTransaction(payload, 'indomaret');
-        expect(mockCharge).toHaveBeenCalled();
+        expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-I-001-CBT'
+            })
+        }));
     });
 
     it('should create an alfamart transaction successfully', async () => {
diff --git a/tests/unit/e-wallet.service.test.js b/tests/unit/e-wallet.service.test.js
index 9bc99e8..130cbfa 100644
--- a/tests/unit/e-wallet.service.test.js
+++ b/tests/unit/e-wallet.service.test.js
@@ -17,13 +17,18 @@ const eWalletService = require('../../app/modules/e-wallet/services/e-wallet.ser
 describe('EWalletService', () => {
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create a gopay transaction successfully', async () => {
         const payload = { order_id: 'u-123', external_id: 'INV-G-001', amount: 25000 };
         mockCharge.mockResolvedValue({ status_code: '201' });
         const result = await eWalletService.createTransaction(payload, 'gopay');
-        expect(mockCharge).toHaveBeenCalled();
+        expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-G-001-CBT'
+            })
+        }));
         expect(result.status_code).toBe('201');
     });
 
diff --git a/tests/unit/notification.controller.test.js b/tests/unit/notification.controller.test.js
index aaf2701..833a202 100644
--- a/tests/unit/notification.controller.test.js
+++ b/tests/unit/notification.controller.test.js
@@ -8,17 +8,20 @@ const NotificationController = require('../../app/modules/notification/controlle
 
 describe('NotificationController', () => {
     let mockReq, mockRes;
+    const routerToken = 'TEST_ROUTER_TOKEN';
 
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.ROUTER_CALLBACK_TOKEN = routerToken;
         mockRes = {
             status: jest.fn().mockReturnThis(),
             json: jest.fn().mockReturnThis()
         };
     });
 
-    it('should handle notification successfully', async () => {
+    it('should handle notification successfully when token and signature are valid', async () => {
         mockReq = {
+            headers: { 'x-callback-token': routerToken },
             body: { order_id: 'I-123', transaction_status: 'settlement' }
         };
 
@@ -32,8 +35,22 @@ describe('NotificationController', () => {
         expect(responseHelper.success).toHaveBeenCalledWith(mockRes, expect.stringContaining('Handled'));
     });
 
+    it('should return 401 if x-callback-token is invalid', async () => {
+        mockReq = {
+            headers: { 'x-callback-token': 'wrong-token' },
+            body: {}
+        };
+
+        await NotificationController.handle(mockReq, mockRes);
+
+        expect(responseHelper.error).toHaveBeenCalledWith(mockRes, expect.stringContaining('Unauthorized token'), 401);
+    });
+
     it('should return 403 if signature invalid', async () => {
-        mockReq = { body: { signature_key: 'invalid' } };
+        mockReq = {
+            headers: { 'x-callback-token': routerToken },
+            body: { signature_key: 'invalid' }
+        };
         notificationService.verifySignature.mockReturnValue(false);
 
         await NotificationController.handle(mockReq, mockRes);
@@ -42,7 +59,10 @@ describe('NotificationController', () => {
     });
 
     it('should return error on service error', async () => {
-        mockReq = { body: { order_id: 'I-123' } };
+        mockReq = {
+            headers: { 'x-callback-token': routerToken },
+            body: { order_id: 'I-123' }
+        };
         notificationService.verifySignature.mockReturnValue(true);
         notificationService.processNotification.mockRejectedValue(new Error('DB Error'));
 
diff --git a/tests/unit/paylater.service.test.js b/tests/unit/paylater.service.test.js
index d23a905..a891c8f 100644
--- a/tests/unit/paylater.service.test.js
+++ b/tests/unit/paylater.service.test.js
@@ -18,6 +18,7 @@ const paylaterService = require('../../app/modules/paylater/services/paylater.se
 describe('PayLaterService', () => {
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create an akulaku transaction successfully', async () => {
@@ -25,6 +26,9 @@ describe('PayLaterService', () => {
         mockCharge.mockResolvedValue({ status_code: '201' });
         await paylaterService.createTransaction(payload, 'akulaku');
         expect(mockCharge).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-AK-001-CBT'
+            }),
             payment_type: 'akulaku'
         }));
     });
diff --git a/tests/unit/snap.service.test.js b/tests/unit/snap.service.test.js
index 3973f76..4a0f3d9 100644
--- a/tests/unit/snap.service.test.js
+++ b/tests/unit/snap.service.test.js
@@ -16,13 +16,18 @@ const snapService = require('../../app/modules/snap/services/snap.service');
 describe('SnapService', () => {
     beforeEach(() => {
         jest.clearAllMocks();
+        process.env.PROJECT_ID = 'CBT';
     });
 
     it('should create a snap transaction successfully', async () => {
         const payload = { order_id: 'u-snap', external_id: 'INV-S-001', amount: 100000 };
         mockCreateTransaction.mockResolvedValue({ token: 't-123', redirect_url: 'http://m.com' });
         const result = await snapService.createTransaction(payload);
-        expect(mockCreateTransaction).toHaveBeenCalled();
+        expect(mockCreateTransaction).toHaveBeenCalledWith(expect.objectContaining({
+            transaction_details: expect.objectContaining({
+                order_id: 'INV-S-001-CBT'
+            })
+        }));
         expect(result.token).toBe('t-123');
     });
 });