SMS Notification Error: [631] Mobile network operator error

Issue

SMS message fails to deliver and logs indicate the following error:

Notification Error; [631] Mobile network operator error

Environment

• All versions of xMatters

• SMS Notifications

Answer

This error indicates that a message could not be delivered due to an infrastructure error at the carrier level. The error may resolve without intervention after a short period of time.

To identify which recipients were affected, use the Reports > Notifications report in xMatters. This report lists notification outcomes and will show SMS delivery failures. You can use it to locate failed SMS deliveries and then investigate each affected recipient individually.

If the error persists, or you see repeated failures for the same users or destinations, Submit a Request with Support for investigation.

Fix

Consider using the xMatters mobile app. Although we continue to work with carriers, providers, and aggregators to lobby for the best end-user experience over SMS, we recommend the xMatters mobile app as a more reliable alternative.