Troubleshooting SMS Delivery
When a text fails, the fastest path to a fix is reading the specific error rather than guessing. Here's how to work through it.
The general process
- Find the error. Failed messages show a red error indicator in the conversation thread — click it to see the specific error code.
- Look up what the code means (see the table below, or the fuller Phone System Error Codes reference).
- Fix the underlying cause, not just the symptom.
- Resend and confirm it actually delivers — a fix that clears one error can sometimes surface a second, different one.
Common errors and fixes
| Situation | Likely cause | Fix |
|---|---|---|
| Recipient never gets texts anymore | They replied STOP at some point | Consent was revoked — you need a fresh, explicit opt-in ("START") before messaging them again |
| Message to an international number fails | Sender/recipient country pairing isn't supported on this number | Use a number registered/enabled for that route |
| Nothing sends, account-wide | Account suspended | See Why Your Phone System Access Was Suspended |
| Message to a specific number always fails | It's a landline, which can't receive SMS | Turn on Number Intelligence to catch these before sending, and remove landlines from your list |
| Message silently disappears, no delivery | Carrier filtered it as spam-like (error 30007) | Review your content, remove shortened public links, and confirm A2P registration is complete |
| All sends to US numbers blocked | A2P registration missing on the sending number | Complete A2P registration |
| MMS specifically fails, SMS is fine | Attachment too large | Check against SMS & MMS File Size Limits |
Why the sender number might look different to the recipient
If a contact tells you a text came from a different number than you expected, that's usually carrier-side sender ID rewriting, not a bug on your end — this is especially common when messaging Mexico. See International SMS Compliance.
Reviewing past restrictions
If your account has hit a temporary sending restriction before, Settings > Phone System > Messaging > Restriction History shows a log of when it happened, why (an opt-out rate spike, an error rate spike, or a daily/weekly limit), and the metrics at the time. Reviewing this after an incident helps you catch whether it was a one-off or a pattern in your list quality or content worth fixing.
If you're still stuck
Contact support with the specific error code, the approximate time of the failed send, and the destination number — that's a much faster starting point than "texts aren't sending."
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