diff --git a/src/CacheManager.Core/Internal/CacheReflectionHelper.cs b/src/CacheManager.Core/Internal/CacheReflectionHelper.cs
index fcbc98bf..bca32a10 100644
--- a/src/CacheManager.Core/Internal/CacheReflectionHelper.cs
+++ b/src/CacheManager.Core/Internal/CacheReflectionHelper.cs
@@ -318,7 +318,7 @@ private static void CheckExtends<TValid>(Type type)
                     return;
                 }
 
-                baseType = type.BaseType;
+                baseType = baseType.BaseType;
             }
 
             throw new InvalidOperationException(