After oauth, no code is returned to redirect URL. i do not get any error in my server log too.
I doubt whether my app is not enabled for that country? or any other issue?
Using the RingCentral Phone for Desktop, you can dial or receive test calls, send and receive test SMS or Fax messages in your sandbox environment.
Download RingCentral Phone for Desktop:
Tip: switch to the "sandbox mode" before logging in the app:
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