diff --git a/lib/providers/call.dart b/lib/providers/call.dart
index bbc9fbb..0d60efd 100644
--- a/lib/providers/call.dart
+++ b/lib/providers/call.dart
@@ -400,6 +400,7 @@ class ChatCallProvider extends GetxController {
   }
 
   void disposeRoom() {
+    isBusy.value = false;
     isMounted.value = false;
     isInitialized.value = false;
     current.value = null;
diff --git a/lib/screens/channel/call/call.dart b/lib/screens/channel/call/call.dart
index a690f20..ba17314 100644
--- a/lib/screens/channel/call/call.dart
+++ b/lib/screens/channel/call/call.dart
@@ -246,7 +246,8 @@ class _CallScreenState extends State<CallScreen> with TickerProviderStateMixin {
                                   return Row(
                                     children: [
                                       Text(
-                                        call.channel.value!.name,
+                                        call.channel.value?.name ??
+                                            'unknown'.tr,
                                         style: const TextStyle(
                                           fontWeight: FontWeight.bold,
                                         ),
diff --git a/lib/translations/en_us.dart b/lib/translations/en_us.dart
index cbfbeb6..a91e332 100644
--- a/lib/translations/en_us.dart
+++ b/lib/translations/en_us.dart
@@ -380,4 +380,5 @@ const i18nEnglish = {
   'messageOutOfSyncCaption':
       'Since the App has entered the background, there may be a time difference between the message list and the server. Click to Refresh.',
   'messageHistoryWipe': 'Wipe local message history',
+  'unknown': 'Unknown',
 };
diff --git a/lib/translations/zh_cn.dart b/lib/translations/zh_cn.dart
index ecb73d2..7f54f02 100644
--- a/lib/translations/zh_cn.dart
+++ b/lib/translations/zh_cn.dart
@@ -346,4 +346,5 @@ const i18nSimplifiedChinese = {
   'messageOutOfSync': '消息可能与服务器脱节',
   'messageOutOfSyncCaption': '由于 App 进入后台，消息列表可能与服务器存在时差，点击刷新。',
   'messageHistoryWipe': '清除消息记录',
+  'unknown': '未知',
 };
diff --git a/lib/widgets/channel/channel_call_indicator.dart b/lib/widgets/channel/channel_call_indicator.dart
index ef57ead..9cb050a 100644
--- a/lib/widgets/channel/channel_call_indicator.dart
+++ b/lib/widgets/channel/channel_call_indicator.dart
@@ -31,6 +31,7 @@ class ChannelCallIndicator extends StatelessWidget {
       builder: (context) => ChatCallPrejoinPopup(
         ongoingCall: ongoingCall,
         channel: channel,
+        onJoin: onJoin,
       ),
     );
   }
diff --git a/lib/widgets/chat/call/call_prejoin.dart b/lib/widgets/chat/call/call_prejoin.dart
index 61efc36..9fe1509 100644
--- a/lib/widgets/chat/call/call_prejoin.dart
+++ b/lib/widgets/chat/call/call_prejoin.dart
@@ -11,11 +11,13 @@ import 'package:solian/providers/call.dart';
 class ChatCallPrejoinPopup extends StatefulWidget {
   final Call ongoingCall;
   final Channel channel;
+  final Function onJoin;
 
   const ChatCallPrejoinPopup({
     super.key,
     required this.ongoingCall,
     required this.channel,
+    required this.onJoin,
   });
 
   @override
@@ -56,6 +58,7 @@ class _ChatCallPrejoinPopupState extends State<ChatCallPrejoinPopup> {
       context.showErrorDialog(e);
     }
 
+    widget.onJoin();
     setState(() => _isBusy = false);
   }