[Urgent] Msg: "We've disabled this app for violating the Meta Platform Terms and Developer Policies. You can continue to use it in development mode. Read more or appeal"

Our app currently cannot allow user to use "Facebook login" as our engineers found that our app has been disabled in production in Facebook (Meta), not sure what problems / issues have been facing here and we'd like to follow up with your end to know more as it's critical for continue to have our users to login our app with Facebook.
We only see the message of "We've disabled this app for violating the Meta Platform Terms and Developer Policies. You can continue to use it in development mode. Read more or appeal"
However, when we clicked "appeal", there's no app being displayed at all on that page so there is no way for us to appeal or understanding what are the issues there. And I'm already the app administrator and also I've checked with several other app admins for the app and we all could not see any information on the appeal page. Please advise what might be the issue and how we can resolve it so that our users can continue to use Facebook Login in our app?