diff --git a/app/core/plugin.py b/app/core/plugin.py
index 5455c0ca..0dfb289d 100644
--- a/app/core/plugin.py
+++ b/app/core/plugin.py
@@ -1102,7 +1102,7 @@ class PluginManager(metaclass=Singleton):
             success, msg = self._modify_plugin_files(
                 plugin_dir=clone_plugin_dir,
                 original_id=plugin_id,
-                suffix=suffix,
+                suffix=suffix.lower(),
                 name=name,
                 description=description,
                 version=version,