Watch series 1

First force restart it

i.e. press and hold both the side button and Digital Crown for at least 10 seconds, then release both buttons when you see the Apple logo.

If that is no help erase the watch with Settings, General, reset, erase all content

and then

Set up your Apple Watch

 If you cannot do any of that Contact Support.

Click here > Contact - Official Apple Support

or phone numbers 

Click here > Contact Apple for support and service - Apple Support

Contact Apple Support in your country if it is not under western sanctions due to the russian war.

Good luck.

Seties 1 is no longer serviced. Buy a new one if Apple are still operating in Russia

Without us speaking Russian we don't know what the problem says. Google translate doesn't work on photo.