W H Y ?
The API reference "Try it out" has not yet been changed to authenticate your app using JWT token. If you wish to use your app for just trying API out, create an app with password flow authentication for that purpose. If you still wish to use your current app for this, give me the app client id. I will also enable the password flow for the app so you can use both authentication methods.
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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