Outage in Cisco Duo

T-Mobile Services SMS Delivery Issue

Resolved Minor

August 26, 2025 - Started 8 months ago - Lasted about 4 hours
Official incident page

Incident Report

We are currently investigating an issue affecting SMS delivery to phone numbers using T-Mobile Services in the US. Please feel free to check back here or subscribe to updates for the latest information regarding any changes or resolutions.

Components affected

Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery Cisco Duo SMS Message Delivery

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Latest Updates ( sorted recent to last )

RESOLVED 8 months ago - at 08/26/2025 10:21AM

Duo has confirmed that the issue affecting SMS delivery to phone numbers using T-Mobile services in the US has been fully resolved.

MONITORING 8 months ago - at 08/26/2025 08:14AM

We are starting to see recovery post the fix implemented by our service provider for the issue affecting SMS delivery to phone numbers using T-Mobile Services in the US.

Please feel free to check back here or subscribe to updates for the latest information regarding any changes or resolutions.

IDENTIFIED 8 months ago - at 08/26/2025 08:02AM

We have detected the issue affecting SMS delivery to phone numbers using T-Mobile Services in the US.
Please feel free to check back here or subscribe to updates for the latest information regarding any changes or resolutions.

INVESTIGATING 8 months ago - at 08/26/2025 06:29AM

We are currently investigating an issue affecting SMS delivery to phone numbers using T-Mobile Services in the US.

Please feel free to check back here or subscribe to updates for the latest information regarding any changes or resolutions.

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