Apple Watch зависли на яблоке

Did you try to force restart by pressing and holding the Digital Crown and the Side button together for about 10sec, until the Apple logo comes back again?

If this does not work, your watch probably has been damaged by water and has to be replaced:

Apple Watch Service and Repair - Apple Support

Have you been swimming lately with your watch?

Has the battery ever been replaced by Apple? Depending on the age and use of the watch, the battery might have to be replaced by Apple.

Apple Watch Service and Repair - Apple Support

Then you will have to get the watch serviced.

The seals of the watch may lose their function over time, depending on the use of the watch.