If your Apple Watch keeps locking, it can be very irritating. There are a few steps that might help, including reviewing settings and cleaning sensors; as well as changing how you wear it. One common cause may be enabled Auto Lock feature in settings app and is designed to protect personal information by locking the display after some inactivity period has passed.
An additional possibility is that the wrist detection feature is malfunctioning. This may occur if dark-colored tattoos on your wrist interfere with sensors, causing the watch to lock incorrectly; or by wearing your watch too tightly as this prevents sensors from properly identifying your wrist.
Back of Watch Can Get Dirty To Fix Wrist Detection Issues
When worn too far up on an arm, above wrist bone level, wrist detection stops working correctly and must be cleaned with damp cloth or soft bristle brush to work effectively again. Some users have reported their watches would lock if worn too far up for their wrist bone; to remedy this situation simply bend closer towards wristbone level until this issue is solved.
If none of these solutions work, resetting and wiping out all content on your Apple watch may be necessary to restore its proper workings. Doing this will reset the passcode and wrist detection settings but make using your watch much simpler as no password needs to be entered each time.