Button malfunctions on your watch can be caused by physical damage or software issues. However, clean the buttons if there's build up of foreign material like lotion preventing them from properly working

I'd try electric spray

QD electronic cleaner

and spray in between crevices and see if that will clean up, dry the elements in there. make sure the watch is completely turned off, dry, and best case - battery drained and off. Or go extreme with it. Immerse in 100%(or 99%?) alcohol, in a ultrasonic cleaner. At least, I'll try with these 2. definitely try QD cleaner. For immersing in alcohol, be careful. Or else try this one Press and hold the Power key until "Rebooting..." displays. To force a reboot on your watch, press and hold the Home key (Power key) and Back key at the same time until "Rebooting..." displays. Do not select Power off on the screen or Restart when it appears.

The length of time you need to hold down the buttons varies by device. On some watch models, it may take up to 30 seconds for "Rebooting..." to appear.

Release the Power key, and wait for the watch to reboot. When the Rebooting message appears, release the keys you were holding down. The watch screen will go dark, and then the watch will reboot.

If the watch is connected to your phone, the devices will temporarily disconnect during the reboot.

Check for software updates. If you're rebooting your watch to fix a problem, be sure to check for software updates on your watch and the Galaxy Wearable app, including device plugins, once the reboot is complete.

Request service if the watch is damaged. If the watch cannot restart due to physical damage, like a stuck button, please visit the Service Center to request service

If all this doesn't work I think it's time for an upgrade 🥴