# SMS Delivery — Encoding Issues on Outbound Messages to T-Mobile

- Provider: [Telnyx](https://down.guide/providers/telnyx)
- Confidence: Confirmed
- Impact: Degraded
- lasted 2d 18h
- started 2026-09-15 21:57 UTC
- NORAM
- id: DWN-79aef1ae56
- Official page: https://status.telnyx.com/incidents/01M2KH64TSCWV2DKT2JD9RFQ0W

## Updates from Telnyx
### 2026-09-15 21:57 UTC: investigating
We are currently investigating reports of encoding issues affecting a subset of outbound SMS messages to T-Mobile. End users may be receiving messages with garbled or unreadable text. We are actively investigating with our downstream partner and will provide an update as soon as we have more information.

### 2026-09-16 21:57 UTC: monitoring
Our downstream partner has deployed a fix for garbled message bodies on 10DLC SMS to T-Mobile destinations. The issue impacted 10DLC senders assigned to 501(c)(3) tax-exempt campaigns predominantly. Test messages to T-Mobile destinations are now delivering intact.

### 2026-09-18 16:26 UTC: resolved
Our downstream partner's fix for garbled message bodies on 10DLC SMS to T-Mobile destinations has been confirmed. Impact was limited to 10DLC senders assigned to 501(c)(3) tax-exempt campaigns. Both test and live traffic to T-Mobile destinations are delivering intact. An RCA will follow.

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