I had this issue (or so I thought) with using a button on a dashboard. It seems, I only thought I was hitting the button. The button action was not showing when I tapped it on my dashboard.
I changed to using the option of turning on a switch instead of using a button. Then, made the switch auto-off after 1 second so I could visibly see the switch turn on and then off on the dashboard.
I have had this behavior in the past. My guess is it's a sneaky bug that only shows up under certain circumstances &/or and a particular combo of devices. This drove me nuts to the point i built a dashboard with my 8 sirens to manually turn them off. The last 6 months it's been okay...
I have the same bug. I use Audio Alert with Message to Speak on amazon echo devices when smoke or water leak is detected. Somes months ago when I cancelled the alarm all message on Echo device stopped. Recently the messages don't stop after the HSM alarme is cancelled even if I checked the "Repeat this alert message until cancelled" is enabled.
Today I test it again and the messages on echo device had finally stopped aprox 20 minutes after I cancelled the alarm...
The problem is still there, the delete command is recorded correctly in the log (even several times), but with no effect. it's like it can't delete the queue. You have to uncheck the repeat option, otherwise it becomes irritating.