Twilio Message Failure Incidents

Way To Health (W2H) acts as the configuration portal for programs to define their conversational logic. The actual delivery of the text messages is done by an external vendor who connects to all the cell carriers - AT&T, Verizon, T-Mobile and many more. The vendor we use currently and that is the largest such out there is Twilio (https://twilio.com ).

W2H generates a Message Failure incident when a message fails to be delivered to a participant, and the incident message includes the Twilio error code indicating why it failed to send. The most common error codes, their meaning, and what you can do about them, are described below.

Error #

Name & Twilio Link

Meaning

Troubleshooting

Can W2H do anything about this error?

Error #

Name & Twilio Link

Meaning

Troubleshooting

Can W2H do anything about this error?

30003

Unreachable Destination Handset

The phone number is unavailable or unreachable

Confirm the following with the participant:

  • Device is powered on

  • Device has sufficient cell signal and is on the home carrier (not roaming or in an area with low coverage, i.e. international travel)

  • Device receives text messages from other numbers

  • If the participant’s carrier is T-Mobile, confirm that Mobile Blocking is not enabled.

    • The participant must call 611 directly from their T-Mobile device experiencing the issue – or if using another device, call 1-800-937-8997 – and request "Shortcode Blocklist" setting to be removed from their account.

No

30005

Unknown Destination Handset

The phone number is unknown, inactive, or no longer in service

No

30006

Landline or unreachable carrier

The phone number is a landline or the destination carrier is unreachable

Contact participant.

  • If the number is a landline, ask them to provide a cell # and add that number to their profile. If they don’t have a cell #, then they cannot participate in a text-based intervention

  • If the number is actually a cell line, follow the troubleshooting instructions above for errors 30003 & 30005

No

30007

Message Filtered (Formerly: Carrier Violation)

The message was blocked by Twilio or the carrier because the content seems like spam, fraud, or abuse.

Identify 3+ participants impacted in the last 72 hours. Submit a help desk ticket at support.waytohealth.org with the blocked message content & W2H IDs for impacted participants. W2H support will work with you to update your messaging language to reduce or eliminate ongoing filtering.

Yes

If you encounter a message failure incident from Twilio that isn't on this list, please visit their website https://www.twilio.com/docs/api/errors#3-anchor to find out more.