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Error 21212

ERROR - 21212

Invalid 'From' Phone Number (caller ID)

You attempted to initiate an outbound phone call or message, but the 'From' parameter you supplied was not a valid phone number or alphanumeric sender ID.

Possible Causes

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 up to 11 alphanumeric characters [a-zA-Z0-9]. The number must not be on the do-not-originate (DNO) list.

Possible Solutions

Inspect the 'From' number

https://en.wikipedia.org/wiki/North_American_Numbering_Plan

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