diff --git a/.github/workflows/test-memory.yml b/.github/workflows/test-memory.yml
index 4081c93a..dc79b913 100644
--- a/.github/workflows/test-memory.yml
+++ b/.github/workflows/test-memory.yml
@@ -1,5 +1,5 @@
 on: [push, pull_request]
-name: Test
+name: Memory Test
 jobs:
   Build:
     strategy:
diff --git a/mongodb/mongodb.go b/mongodb/mongodb.go
index bcec7959..8e9a9012 100644
--- a/mongodb/mongodb.go
+++ b/mongodb/mongodb.go
@@ -104,6 +104,9 @@ func (s *Storage) Get(key string) ([]byte, error) {
 	item := s.acquireItem()
 
 	if err := res.Err(); err != nil {
+		if err == mongo.ErrNoDocuments {
+			return nil, ErrNotExist
+		}
 		return nil, err
 	}
 	if err := res.Decode(&item); err != nil {
@@ -111,7 +114,7 @@ func (s *Storage) Get(key string) ([]byte, error) {
 	}
 
 	if !item.Expiration.IsZero() && item.Expiration.Unix() <= time.Now().Unix() {
-		return nil, nil
+		return nil, ErrNotExist
 	}
 	// // not safe?
 	// res := item.Val