When you say you replaced the joycon, do you mean you replaced the joystick with the gulikit joystick from the shop? If you've replace that and the daughterboard of the offending joycon and you're getting the same issue, it sounds like your switch lite may have some sort of issue either with the main board or some software glitch (though in my experience issues like this are almost always rooted in hardware). Where you've already reset it and calibrated everything, I'd definitely lean towards a hardware glitch with your switch. I'd reach out to Nintendo to see if they have any insight into the issue.