Authorization request failed with reason "invalid_grant"

When I attempt to get authorization token I get 400 error. I pass in the following info:

  • client id
  • team id
  • key identifier
  • client secret
  • access code
  • redirect url

I'm testing this on a launched nodejs backend, and a testflight build of my react native/expo app. I know my code works because I'm using the exact same setup on a different project and it works perfectly.

I'm assuming I'm doing something wrong setting up the keys in apples Certificates, Identifiers & Profiles site, but anything I try doesn't work. Is there clear instructions somewhere on how this should be set up?