Restart Apple Watch
If something isn’t working right, try restarting your Apple Watch and its paired iPhone.
Restart Apple Watch
Turn off your Apple Watch: Press and hold the side button until the sliders appear, then drag the Power Off slider to the right.
Turn on your Apple Watch: Hold down the side button until the Apple logo appears.
Note: You can’t restart your Apple Watch while it’s charging.
Restart the paired iPhone
Turn off your iPhone: Press and hold the side or top button until the slider appears, then drag the slider to the right or go to Settings > General > Shut Down.
Turn on your iPhone: Hold down the side or top button until the Apple logo appears.
Force Apple Watch to restart
If you can’t turn off your Apple Watch or if the problem continues, you may need to force your Apple Watch to restart. Do this only if you’re unable to restart your Apple Watch.
To force restart, hold down the side button and the Digital Crown at the same time for at least ten seconds, until the Apple logo appears.