diff --git a/src/layouts/estimate/estimate.vue b/src/layouts/estimate/estimate.vue
index 5ab1df2ae..b9fdf1958 100644
--- a/src/layouts/estimate/estimate.vue
+++ b/src/layouts/estimate/estimate.vue
@@ -145,7 +145,7 @@ export default {
 
             vm.setCmsContent(resultMap.cmsContent);
             if (store.getters.externalParameterState?.isExternalParameter) {
-                if (store.getters.externalParameterCustomer.phoneNumber) {
+                if (store.getters.externalParameterCustomer?.phoneNumber) {
                     await baseMixin.methods.dispatchStoreAction(
                         storeActions.SAVE_PHONE_NUMBER,
                         store.getters.externalParameterCustomer.phoneNumber,