diff --git a/gitea/gitea.py b/gitea/gitea.py
index 5d10a5c..de38176 100644
--- a/gitea/gitea.py
+++ b/gitea/gitea.py
@@ -150,11 +150,17 @@ class User(GiteaApiObject):
         "website",
     }
 
-    def commit(self):
+    def commit(self, login_name: str, source_id: int = 0):
+        """
+        Unfortunately it is necessary to require the login name
+        as well as the login source (that is not supplied when getting a user) for
+        changing a user.
+        Usually source_id is 0 and the login_name is equal to the username.
+        """
         values = self.get_dirty_fields()
         values.update(
             # api-doc says that the "source_id" is necessary; works without though
-            {"login_name": self.username}
+            {"login_name": login_name, "source_id": source_id}
         )
         args = {"username": self.username}
         self.gitea.requests_patch(User.ADMIN_EDIT_USER.format(**args), data=values)
diff --git a/tests/test_api.py b/tests/test_api.py
index 486b584..2d09444 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -69,7 +69,7 @@ def test_change_user(instance):
     user.location = location
     new_fullname = "Other Test Full Name"
     user.full_name = new_fullname
-    user.commit()
+    user.commit(user.username, 0)
     del(user)
     user = instance.get_user_by_name(test_user)
     assert user.full_name == new_fullname