I have been unable to satisfy the webhook subscription graduation requirement. I have tried create, read, update, delete and renew. Please see Client Id: AnI0YZU5QD2XF3hGwkJ3cg
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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