diff --git a/src/controllers/customer-branch-controller.ts b/src/controllers/customer-branch-controller.ts
index a9cf867..c6ed578 100644
--- a/src/controllers/customer-branch-controller.ts
+++ b/src/controllers/customer-branch-controller.ts
@@ -305,6 +305,17 @@ export class CustomerBranchController extends Controller {
           );
         }
 
+        const last = await tx.runningNo.upsert({
+          where: {
+            key: `CUSTOMER_${customer.code.slice(0, -6)}`,
+          },
+          create: {
+            key: `CUSTOMER_${customer.code.slice(0, -6)}`,
+            value: 1,
+          },
+          update: { value: { increment: 1 } },
+        });
+
         return await tx.customerBranch.create({
           include: {
             province: true,
@@ -316,7 +327,7 @@ export class CustomerBranchController extends Controller {
           data: {
             ...rest,
             statusOrder: +(rest.status === "INACTIVE"),
-            code: `${customer.code}-${rest.branchNo.toString().padStart(2, "0")}`,
+            code: `${customer.code.slice(0, -6)}${`${last.value - 1}`.padStart(6, "0")}`,
             customer: { connect: { id: customerId } },
             province: { connect: provinceId ? { id: provinceId } : undefined },
             district: { connect: districtId ? { id: districtId } : undefined },
diff --git a/src/controllers/customer-controller.ts b/src/controllers/customer-controller.ts
index 5947bb8..a091cfe 100644
--- a/src/controllers/customer-controller.ts
+++ b/src/controllers/customer-controller.ts
@@ -37,6 +37,8 @@ const MANAGE_ROLES = [
 export type CustomerCreate = {
   registeredBranchId?: string;
 
+  code: string;
+
   status?: Status;
   personName: string;
   personNameEN?: string;
@@ -312,15 +314,29 @@ export class CustomerController extends Controller {
       async (tx) => {
         const last = await tx.runningNo.upsert({
           where: {
-            key: `CUSTOMER_${body.customerType}`,
+            key: `CUSTOMER_${body.code.toLocaleUpperCase()}`,
           },
           create: {
-            key: `CUSTOMER_${body.customerType}`,
+            key: `CUSTOMER_${body.code.toLocaleUpperCase()}`,
             value: 1,
           },
-          update: { value: { increment: 1 } },
+          update: { value: { increment: (body.customerBranch?.length || 0) + 1 } },
         });
 
+        body.code = body.code.toLocaleUpperCase();
+
+        const exist = await tx.customer.findFirst({
+          where: { code: `${body.code}000000` },
+        });
+
+        if (exist) {
+          throw new HttpError(
+            HttpStatus.BAD_REQUEST,
+            "Customer with same code already exists.",
+            "sameCustomerCodeExists",
+          );
+        }
+
         return await prisma.customer.create({
           include: {
             branch: {
@@ -336,13 +352,13 @@ export class CustomerController extends Controller {
           data: {
             ...payload,
             statusOrder: +(payload.status === "INACTIVE"),
-            code: `${last.key.slice(9)}${last.value.toString().padStart(6, "0")}`,
+            code: `${body.code}000000`,
             branch: {
               createMany: {
                 data:
-                  customerBranch?.map((v) => ({
+                  customerBranch?.map((v, i) => ({
                     ...v,
-                    code: `${last.key.slice(9)}${last.value.toString().padStart(6, "0")}-${v.branchNo.toString().padStart(2, "0")}`,
+                    code: `${body.code}${`${last.value - customerBranch?.length + i + 2}`.padStart(6, "0")}`,
                     createdByUserId: req.user.sub,
                     updatedByUserId: req.user.sub,
                   })) || [],