diff --git a/src/stores/customer/types.ts b/src/stores/customer/types.ts
index 71410100..9b3724c0 100644
--- a/src/stores/customer/types.ts
+++ b/src/stores/customer/types.ts
@@ -21,7 +21,7 @@ export type CustomerBranchCreate = {
 
   legalPersonNo: string;
 
-  taxNo: string;
+  taxNo?: string | null;
   name: string;
   nameEN: string;
   addressEN: string;