diff --git a/src/ReverseProxy/Utilities/CaseSensitiveEqualHelper.cs b/src/ReverseProxy/Utilities/CaseSensitiveEqualHelper.cs
index b9293baa8..57ad8f660 100644
--- a/src/ReverseProxy/Utilities/CaseSensitiveEqualHelper.cs
+++ b/src/ReverseProxy/Utilities/CaseSensitiveEqualHelper.cs
@@ -15,7 +15,7 @@ internal static bool Equals(IReadOnlyList<string> list1, IReadOnlyList<string> l
                 return true;
             }
 
-            if (list1 == null && list2 == null)
+            if (list1 == null || list2 == null)
             {
                 return false;
             }