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Attempt to send to unsubscribed recipient



ERROR: 21610

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PROGRAMMABLE SMS
ERROR

The person you are trying to message has opted out of receiving messages from your Twilio phone number, Channels sender, or Messaging Service.

You have attempted to message a 'To' number that has replied with "STOP" to one of your previous messages. You will not be able to send to the phone number specified in the 'To' parameter until the subscriber identified by the phone number has responded with "START".

Please see this FAQ(link takes you to an external page) for more information about how Twilio handles opt-out and opt-in.

Possible Causes

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