See here to clean the laser lens protector.
If the 10W laser emitter does not recover its cutting capability after you clean the laser lens protector, the laser lens protector may be broken. You can replace the laser lens protector and check if the problem persists.
If the 10W laser emitter does not recover its cutting capability after you replace the laser lens protector, the 10W laser emitter may be broken. Please contact us at support@snapmaker.com for maintenance or replacement.