Why doesn't my Apple Watch ring when my iPhone rings?
Why doesn’t my I watch ring when my phone does
[Re-Titled by Moderator]
Original Title: Watch not ringing
Apple Watch SE, watchOS 11
Did you make sure, that in your Watch App on your iPhone -> My Watch -> Phone -> "Mirror my iPhone" is selected and Sound & Haptic for Ringtones?
If this worked in the past, force restarting your devices may help.
Force restart iPhone - Apple Support
To force restart your watch, press and hold the Digital Crown and the Side button together for about 10sec, until the Apple logo comes back again.