diff --git a/bemani/frontend/mga/endpoints.py b/bemani/frontend/mga/endpoints.py
index e9a8f1b..16db8d6 100644
--- a/bemani/frontend/mga/endpoints.py
+++ b/bemani/frontend/mga/endpoints.py
@@ -129,7 +129,7 @@ def updatename() -> Dict[str, Any]:
         "a-z" +
         "A-Z" +
         "0-9" +
-        "@!?/=():*^[\]#;\-_{}$.+" +
+        "@!?/=():*^[\\]#;\\-_{}$.+" +
         "]*$",
         name,
     ) is None: