Smart Watch

Try resetting the Watch. Press and hold the Digital Crown and power button together until you see the Apple logo and then release. The Watch will reboot. Test it then. If that does not help, try changing your Watch face. Some people reporting this problem have reported this helping resolve the problem. If you are able to change the Watch face and that allows you to swipe up, then try setting your Watch face back and it should work. If it does not, then you will need to unpair your Watch from your iPhone, which will create a backup of the Watch. Wipe the Watch, then pair the Watch to your iPhone again. Unpair and erase your Apple Watch - Apple Support then pair it again. Set up your Apple Watch - Apple Support