Obviously reviewer is asking to provide evidences that you have a right to stream audio/video content your app is streaming :) You can provide by attaching legal licenses to stream the content you own.

@itisalex what was changed? How did you achieved to pass review?

Don't swallow exceptions! I recommend you instead "return null" show error dialog (so app reviewer can provide screenshot with all details) and/or log it somewhere remotely. I see you're using Flutter, pobably Firebase? Then you can use FirebaseAnalytics (firebase_analytics package) that can log error so you can see all details in Firebase Console

@qiuping345 I am just curious, have you received answer about your appeal? If yes, how many total days it tool? We also submitted appeal, haven't received any confirmation/tracking id and thinking can it be lost...