diff --git a/Source/Game/Maps/GridNotifiers.cs b/Source/Game/Maps/GridNotifiers.cs
index ff2a6c2d6..5e40d19c9 100644
--- a/Source/Game/Maps/GridNotifiers.cs
+++ b/Source/Game/Maps/GridNotifiers.cs
@@ -2460,7 +2460,7 @@ namespace Game.Maps
             if (i_args.CreatureId.HasValue && u.GetEntry() != i_args.CreatureId)
                 return false;
 
-            if (i_args.StringId != null && u.HasStringId(i_args.StringId))
+            if (i_args.StringId != null && !u.HasStringId(i_args.StringId))
                 return false;
 
             if (i_args.IsAlive.HasValue && u.IsAlive() != i_args.IsAlive)