HomePod Mini timer does not ring when time runs out

Timers have stopped working on one of my HomePod minis. I can set a timer in the home app and by asking Siri. Siri also responds with a confirmation. The timer countdown is visible in the home app, but when the time is up, there is no sound. The "00:00" number and pause button remain visible on the HomePod app window until I close and reopen it. I have unplugged, replugged the HomePod from the power source and reset the HomePod using the home app. Just now the timer rang, without any timer being visible in the home app (Seems like it was a timer I set before resetting the HomePod). Timers are still working on my other three HomePods.