Apple Sign-in Signup not completed

[ashrafemad]

I've followed all steps mentioned here:
https://python-social-auth.readthedocs.io/en/latest/backends/apple.html?highlight=apple#appleid

when i visit my endpoint GET https://domain.com/api/v1/apple-id/ from a non-apple device i get invalid redirect_uri while I'm sure that we used the correct redirect uri in Apple's dashboard which is https://domain.com/api/v1/complete/apple-id/

and when tried it on an Iphone i got Signup not completed popup error, and found this in Apple Forums https://developer.apple.com/forums/thread/122458

what could be the issue?