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Invalid 'From' Number



ERROR: 21212

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ERROR

You attempted to initiate an outbound phone call or message, but the From parameter you supplied was not a valid phone number, Alphanumeric Sender ID or approved WhatsApp Sender.

Twilio accepts phone numbers in E.164 format (i.e. "+1 format"), 10-digit US and Canadian numbers with any combination of non-digit separators, or Alphanumeric Sender IDs (SMS only) with up to 11 alphanumeric characters [a-zA-Z0-9]. Refer to this page(link takes you to an external page) for acceptable characters.

The number must not be on a do-not-originate (DNO) list, and Alphanumeric Sender IDs may not be generic.

Possible Causes

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  • You have supplied a phone number that was not in E.164 format.
  • Your From phone number is on a do-not-originate (DNO) list.
  • Your Alphanumeric Sender ID is blocked or too generic.
  • You are trying to use an Alphanumeric Sender ID on Trial Account. Trial accounts cannot send from Alphanumeric Sender IDs.
  • Your WhatsApp Sender is not approved.
  • You attempted to send a message with a From number that has an invalid prefix, using a Messaging Service.

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