diff --git a/constant/chat.go b/constant/chat.go
index 336a5cdc..3eecb9d5 100644
--- a/constant/chat.go
+++ b/constant/chat.go
@@ -21,6 +21,7 @@ var Chats = []map[string]string{
 }
 
 func UpdateChatsByJsonString(jsonString string) error {
+	Chats = make([]map[string]string, 0)
 	return json.Unmarshal([]byte(jsonString), &Chats)
 }