I have the same. Both for repeating alarms ad for one time alarms.
If you reboot the watch, the time is shown on the watch face, but after you scroll through widgets or so ething else it’s gone again.
I reported it to Suunto.
Have to say, I have less of a need to show it on my watchface. Before this update I had an alarm for workdays, but had to disable that on Thursday eve and remember to enable it again before Sunday eve. Now I can just set an alarm for Monday till Thursday.