Code Verifier issue

[Chakit22]

1. Even after using the same algorithm used in the code I seem to get the error
   {"error":"invalid_grant","error_description":"code_verifier was incorrect"}.

2. I followed the same steps mentioned in the code and then too I get this error.

[JesusAcostaCabrera]

I'm having the same issue. I've been trying user auth and can't even retrieve user's profile.