diff --git a/src/client.ts b/src/client.ts
index e55cec3..981f9e7 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -146,7 +146,7 @@ export class FakeRTCClient extends FakeAgoraEventEmitter {
     this.uid = randUuid();
     // eslint-disable-next-line @typescript-eslint/ban-ts-comment
     //@ts-ignore websdk的私有属性
-    this._joinInfo?.uid = this.uid;
+    this._joinInfo.uid = this.uid;
     this.channelName = FAKE_CHANNEL_NAME;
     return Promise.resolve(this.uid);
   }