diff --git a/src/pages/03_customer-management/form.ts b/src/pages/03_customer-management/form.ts
index b11657a0..51e5a4f5 100644
--- a/src/pages/03_customer-management/form.ts
+++ b/src/pages/03_customer-management/form.ts
@@ -399,7 +399,7 @@ export const useCustomerBranchForm = defineStore('form-customer-branch', () => {
     lastNameEN: '',
     telephoneNo: '',
     gender: '',
-    birthDate: '',
+    birthDate: undefined,
 
     businessType: '',
     jobPosition: '',
@@ -434,7 +434,7 @@ export const useCustomerBranchForm = defineStore('form-customer-branch', () => {
     customerName: '',
     registerName: '',
     registerNameEN: '',
-    registerDate: null,
+    registerDate: undefined,
     authorizedCapital: '',
     authorizedName: '',
     authorizedNameEN: '',