The Pingdom site reliability engineering and dev team has identified a buildup in the webhook alerting queue between 15:25-15:52 UTC.

This has affected alerts sent via webhook (mainly to Slack and other third party alerting services) but we estimate that less than 50 alerts in total have been affected. The alerts have been sent, but with a delay.

The issue has been fixed and the root cause of the problem is being addressed to prevent this from happening again in the future.

Sorry about this, please get in touch if you have any questions or concerns about this or anything else in Pingdom.