I have a team scoped app and it was working just fine. Starting from yesterday, authorization (token_access_type=offline&response_type=code) fails with:
Error connecting app
There was an error processing the request, please refresh the page and try again.
Login account is team admin and has a personal account linked.
I tested with another team admin without a personal account linked and was able to proceed to get the authorization code. When I add link to personal account to it and try OAuth again, the error is hit.