diff --git a/src/server/game/Grids/Notifiers/GridNotifiers.h b/src/server/game/Grids/Notifiers/GridNotifiers.h
index 9f59510e29..c7b79eb0b6 100644
--- a/src/server/game/Grids/Notifiers/GridNotifiers.h
+++ b/src/server/game/Grids/Notifiers/GridNotifiers.h
@@ -1490,7 +1490,7 @@ namespace Trinity
                 if (i_args.CreatureId && u->GetEntry() != i_args.CreatureId)
                     return false;
 
-                if (i_args.StringId && u->HasStringId(*i_args.StringId))
+                if (i_args.StringId && !u->HasStringId(*i_args.StringId))
                     return false;
 
                 if (i_args.IsAlive.has_value() && u->IsAlive() != i_args.IsAlive)