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  • What are the restrictions on caller ID?

    You must use Plivo phone numbers as the caller ID for your outbound calls. We no longer support using a non-Plivo number as the caller ID. We’ve implemented this restriction to prevent fraud and ensure compliance with the guidelines set by our operators.

    If you attempt to use a non-Plivo number as the caller ID for outbound calls, your calls may fail with a hangup cause of “unknown_caller_id.”  Our documentation provides more information on Zentrunk hangup causes.

    You have two options to obtain Plivo numbers: You can rent numbers through the Plivo console or use our Buy a Phone Number API to acquire new numbers. If you have existing numbers, you can port them to Plivo, ensuring seamless connectivity for your outbound calls.

    If you have a use case that requires the use of a non-Plivo number as the caller ID, please contact our support team for assistance. We’ll help you find a solution that meets your requirements.