On February 5th at 4:29PM to 4:56PM PST, some customers were not able to send messages through Slack's API.
At 4:29PM PST, we deployed a change which affected caching for our Slack API apps resulting in a database becoming unavailable. This caused some messages sent via the API to fail. At 4:56 PM PST we deployed a revert for the change and resolved the issue.
If you notice any further issues with sending messages through the API, please let us know at firstname.lastname@example.org.
4:56 PM PST