diff --git a/backend/src/main/java/online/wesal/wesal/controller/PuzzleController.java b/backend/src/main/java/online/wesal/wesal/controller/PuzzleController.java
index a35aab3..6e3c10b 100644
--- a/backend/src/main/java/online/wesal/wesal/controller/PuzzleController.java
+++ b/backend/src/main/java/online/wesal/wesal/controller/PuzzleController.java
@@ -16,6 +16,7 @@ import org.springframework.web.bind.annotation.*;
 
 import java.time.LocalDateTime;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.stream.Collectors;