Oauth integration not working after appwrite upgrade 1.6.0 -> 1.6.1

Hey all,
I hope this is the correct category.

As the title states, we recently upgraded both our staging and production appwrite to 1.6.1.
We had GitHub oauth enabled on both and in both the GitHub oauth login doesn't work anymore.

The error states it's a faulty input, but nothing was changed in either configuration.

Any hints on what could be the issue are much appreciated

Accounts from other people singing up with GitHub are coming in, so maybe it has to do with someone signing up again after removing his account.