The issue has been working for the last few hours. Cached message statuses have also been fixed.
Posted Aug 15, 2023 - 17:44 UTC
Fix is deployed. It'll only fix it for new messages, fixing it for older ones (fixing the status cache there) will come in a bit.
Posted Aug 15, 2023 - 15:01 UTC
We got a few reports of an issue that some webhooks are showing as "sending" even though they successfully got sent. A fix is on the way, sorry about that. It doesn't affect actual webhook delivery, it's just the UI that's affected.