I am new to RingCentral and using the JWT auth method.
I have followed the instructions in your developer guide (https://developers.ringcentral.com/guide/authentication/jwt-flow) regarding JWT authentication. I am trying to get an access token but am getting the error:
Expected HTTP Error: Refresh token has expired
Here is my code
My client id - RQzC-BTETXqUOVyl_sUHsw'
Please help me. I don't know what I am doing wrong.