My Apple Watch series 7 suddenly after 1 week has no sound at all!! I tried all speakable applications, calls, notification, Siri and even find my when I choose to play a sound there is no sound played.

It looks like a bug, the sound and haptics were completely off (maybe after installing new apps), I checked all settings but the watch remains silenced and I missed to wake up for catching train. I thought it was due to some conflicts with sleep mode, my sleep tracking app and the theatre mode but no, nothing seems to have sound management option that conflict with each other. I decided to uninstall my sleep app, delete all sleep schedule, go to setting and change sound levels but the watch remains completely silent.

At the end a simple reboot, turning off the watch and restart fixed the problem, suddenly my watch came back to life.

Please Apple, look at this issue, it seems to be a bug, it will be nice to fix that in the next OS release.

Thanks.

On your iPhone, open the Apple Watch App > Sounds & Haptics

Is Silent Mode enabled by chance?

Where is the volume slider set?

Periodically any computing device requires restart/reboot. Laptops, Cell Phones, Tablets, Smart Devices, etc.

I wouldn't be upset you needed to reboot your watch to get something unstuck.