It means a server has rejected a request because the message content format is not supported.
I read that this is referring to the headers Content-Type. But what I have there is right from Spotifys documentation.
I changed the body type to JSON and now its giving me this error:
Status code 400
{“error”:“unsupported_grant_type”,“error_description”:“grant_type parameter is missing”}
But Spotifys documentation says this to enter “authorization_code” which is what I have.