fix(dubbo-server): add group default ''
diff --git a/packages/dubbo/src/server/server.ts b/packages/dubbo/src/server/server.ts
index afb0a4a..11bdc3a 100644
--- a/packages/dubbo/src/server/server.ts
+++ b/packages/dubbo/src/server/server.ts
@@ -226,7 +226,7 @@
   private matchService(request: Request) {
     const {methodName} = request;
     const {
-      attachment: {path, group, version},
+      attachment: {path, group = '', version},
     } = request;
 
     const service = this._serviceMap.get(path);