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Error 63003 "Channel could not find To address" when Sending Programmable Messages to Channels

If a message you sent to a Programmable Messaging Channel (WhatsApp, Facebook, Line, etc.) returns a 63003 error code, this means that Twilio was unable to validate the To field value. This guide covers the following topics for diagnosing and resolving your issues:

Please start at the top, and walk through each of the troubleshooting steps as you work your way down the page.

Channel user address

The first step to troubleshooting this issue is to verify your message is addressed to a valid and correctly formatted channel user address. This is what Twilio uses in place of the To phone number when sending messages to Channels like WhatsApp, Facebook, and Line. Some issues that could produce an Error 63003 response include:

  • Using the incorrect channel address format
  • Using a Facebook User ID or an invalid Facebook Messenger ID
  • Using a Line userName or an invalid Channel ID
  • Using an unregistered or invalid e164 phone number for WhatsApp
  • Using a different channel user address to respond than what you received

If you have confirmed you are using a valid channel user address, continue to Verify the destination.

Verify the destination

Next, you will want to validate that your destination is an active user on the Channel service, and able to receive messages. This is most important for unsolicited outbound messages (delivery alerts, appointment reminders, etc.) sent to users who have opted in to receive messages from you, as responses should be from a valid address..

  • Is the destination device powered on and able to receive messages?
  • Does the destination have sufficient signal to browse the web? If not power the device off, wait 30 seconds, and then power it back up and try again.
  • Check to see if the destination user can receive direct messages from you within the Channel's application.
  • If the channel user address contains the destination's phone number, verify it is correct.

If you have confirmed the destination user is able to receive messages, continue to Channel messaging troubleshooting.

Channel messaging troubleshooting

The next step is to rule out any Twilio channel problems. Try sending additional test messages via a REST API request.

  • Check the Twilio Status Page to see if an active incident could be causing your issues.
  • Can you receive incoming messages on this Messaging Channel?
  • Can other users receive your messages on this Messaging Channel?

If you have confirmed that your Twilio channel messaging is working as it should, please Escalate to Twilio Support

Escalate to Twilio Support

If you can rule out all of the above issues, Twilio's Support team can help investigate what went wrong with delivering your Channel messages. Please collect 3 or more examples of messages flagged with Error 63003 in your SMS logs from the last 24 hours, and include the following information:

  • Sending channel endpoint address (from)
  • Destination channel user address (to)
  • Your Twilio project Account SID
  • SMS SIDs (If you have them)
  • Timestamps of message attempts
  • Snippet of code used for sending your message

When you have collected this information, please share it with our Support team.

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