That is not normal behavior. Most Apple devices come with a limited warranty and up to 90 days of complimentary support. Unless you bought additional coverage such as AppleCare or ApplkCare+, I'm sure it is out of warranty. For repair & service:
watch Repair - Official Apple Support
watch Service Pricing - Apple Support
The first (and simplest) thing to try yourself if something isn’t working right is to restart your Apple Watch and its paired iPhone. If necessary (device not responding), try a forced restart. Both methods can be found here:
How to restart your Apple Watch - Apple Support
Restart your iPhone - Apple Support
If that doesn't help, the next steps would be to unpair and pair your watch again and restore from the backup just created. This should result in no loss of data. It deletes all temp and corrupted files and re-indexes the file system.
Unpair and erase your Apple Watch - Apple Support
Set up your Apple Watch - Apple Support