The Touchscreen is not working - what to fix?

I have a Series 1 Apple Watch that just lost touchscreen functionality. The crown and side buttons work, screen still works (except for touch) and it charges fine. However the whole screen itself also has popped up out of the case at the same time. I assume these are related issues. I know it needs to be fixed, but I’m not sure what parts to replace? Should I replace the entire screen? Or is it the touch sensor gasket that is not working? Please help. This is my first time trying to repair on my own. I took it to Best Buy and they told me to just replace it which is a no-go for me. Thanks!