diff --git a/src/components/EditStaff/EditStaff.tsx b/src/components/EditStaff/EditStaff.tsx
index eb62306..9de9f01 100644
--- a/src/components/EditStaff/EditStaff.tsx
+++ b/src/components/EditStaff/EditStaff.tsx
@@ -161,10 +161,16 @@ const EditStaff: React.FC<formProps> = ({ Staff, combos, SalaryEffectiveInfo })
           }))
         }
         // remove useless data
-        if (postData.joinDate === 'Invalid Date') 
+        if (postData.joinDate === 'Invalid Date') {
           postData.joinDate = null
-        if (postData.departDate === 'Invalid Date') 
+        } else {
+          postData.joinDate = dayjs(postData.joinDate).format("YYYY-MM-DD")
+        }
+        if (postData.departDate === 'Invalid Date') {
           postData.departDate = null
+        } else {
+          postData.departDate = dayjs(postData.departDate).format("YYYY-MM-DD")
+        }
         if (!postData.joinPositionId) 
           postData.joinPositionId = null