diff --git a/examples/resources.py b/examples/resources.py
index 8a213b3..ff71a59 100644
--- a/examples/resources.py
+++ b/examples/resources.py
@@ -56,6 +56,7 @@ class AdminResource(Model):
         ),
         "created_at",
     ]
+
     async def get_toolbar_actions(self, request: Request) -> List[ToolbarAction]:
         return []
 
diff --git a/fastapi_admin/providers/login.py b/fastapi_admin/providers/login.py
index 5ad37b8..71754a7 100644
--- a/fastapi_admin/providers/login.py
+++ b/fastapi_admin/providers/login.py
@@ -70,8 +70,11 @@ class UsernamePasswordProvider(Provider):
         signals.pre_save(self.admin_model)(self.pre_save_admin)
 
     async def pre_save_admin(self, _, instance: AbstractAdmin, using_db, update_fields):
-        db_obj = await instance.get(pk=instance.pk)
-        if db_obj.password != instance.password:
+        if instance.pk:
+            db_obj = await instance.get(pk=instance.pk)
+            if db_obj.password != instance.password:
+                instance.password = hash_password(instance.password)
+        else:
             instance.password = hash_password(instance.password)
 
     async def login(self, request: Request, redis: Redis = Depends(get_redis)):