I am using ringcentral api for ringout in Dev sandbox. But unfortunately I am getting exception:
"message": "Forbidden", "errorCode": "InternationalProhibited"
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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