Error 21211 - Twilio
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Error 21211

Error - 21211

Invalid 'To' Phone Number

You attempted to initiate an outbound phone call, but the 'To' phone number you supplied was not a valid phone number. Twilio accepts phone numbers in E164 format (i.e. "+1 format"), or 10-digit US and Canadian numbers with any combination of non-digit separators.

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