diff --git a/dbutils/insert.go b/dbutils/insert.go
index 8963c952..2a7ef8c7 100644
--- a/dbutils/insert.go
+++ b/dbutils/insert.go
@@ -23,8 +23,6 @@ func genRandomTimestamp(now int64, last30d int64) int64 {
 	return rand.Int63n(last30d) + now
 }
 
-const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
-
 func genRandomContentTopic(n int) string {
 	topics := []string{"topic1", "topic2", "topic3", "topic4", "topic5"}
 	i := n % 5
@@ -70,6 +68,10 @@ func main() {
 		fmt.Println("Inserting ", N, " records in ", dbName)
 
 		db, err := newdb(dbName)
+		if err != nil {
+			panic(err)
+		}
+
 		query := "INSERT INTO message (id, receiverTimestamp, senderTimestamp, contentTopic, pubsubTopic, payload, version) VALUES (?, ?, ?, ?, ?, ?, ?)"
 
 		err = createTable(db)
diff --git a/waku/persistence/store.go b/waku/persistence/store.go
index 3ca6e709..c66c028a 100644
--- a/waku/persistence/store.go
+++ b/waku/persistence/store.go
@@ -158,6 +158,11 @@ func (d *DBStore) Put(cursor *pb.Index, pubsubTopic string, message *pb.WakuMess
 		return err
 	}
 
+	err = stmt.Close()
+	if err != nil {
+		return err
+	}
+
 	return nil
 }