Increased error rate of sending SMS alerts
Incident Report for Checkly

After a recent change in our SMS alerting service, we’ve introduced a regression which caused an increased error rate in SMS alert delivery to certain countries (list of affected countries with country codes below). After analysing our logs we determined that alerts were not correctly delivered between 2024-02-06 11:20 UTC and 2024-02-08 09:00 UTC. We’ve implemented a fix and improved the sensitivity of our alarms in the SMS service to prevent similar issues from happening in the future.

We apologize for any problems this may have caused. If you have any questions or concerns feel free to contact us via

List affected countries, country codes

  • Belgium: +32
  • US: +1
  • Brazil: +55
  • Australia: +61
  • Turkey: +90
Posted Feb 08, 2024 - 10:23 UTC

This incident has been resolved.
Posted Feb 08, 2024 - 09:39 UTC
We've identified the issue and updated our config to resolve it. We are monitoring the effectiveness of our fix.
Posted Feb 08, 2024 - 09:02 UTC
We've identified that our SMS alerts in certain countries are not delivered successfully. We are investigating the root cause
Posted Feb 08, 2024 - 08:32 UTC
This incident affected: Alerting.