Home button fast tapping

Hello, yesterday my iPhone started to turn off randomly and quickly after 2 mins of usage, the battery percentage also changes after each reboot, I thought my battery is completely dead at this point, and whenever I try to check for its health the phone reboots.

This happened even when the phone is on sector, and the battery doesn't seem to get charge anymore. I tried to drop the phone multiple times to be sure it's not a bad connector but that didn't turn it off.

Since it was Sunday and I couldn't find any open shop, I decided to disassemble my phone and take a look, I removed the screen and took the chance to clean the rear camera.

I put back all the parts and booted the phone, for some reason the battery now works as it should and the phone doesn't turn off randomly anymore, but unfortunately I had another weird problem.

Whenever I put (not press) on the home button, the reachability option turns on/off quicky as if I'm tapping multiple times, and I cannot even go to home screen because the touch id works only when I put my finger and not tapping, so after few attempts the passcode popped up and I immediately disabled the reachability option.

Now that I removed the flickering, the problem is persisting I just don't see it, what I mean is the phone behaves almost as normal but it feels kinda wrong, anything requiring touch id will not work because even if the reachability is off the phone still detects multiple tapping, I turned off the touch id and tried to access Microsoft Authenticator app, which requires touch id, normally if the phone fails to recognize my fingerprint 3 times it gives me the option to use passcode, but since it's detecting fast tapping, it doesn't even know that I'm resting my finger above the home button trying to access the app, so the passcode option doesn't appear at all...

Today I re-enabled the reachability and it worked fine, I thought that the problem solved itself but it didn't, if I put my finger on the home button for few second nothing happens, but when I do the same thing while I'm inside the 'Touch ID and passcode' settings (even when it's turned off) the flickering reappear, so whenever the touch ID is active it detects multiple tapping.

When I removed the screen, I didn't touch any of its components, just removed the ribbon cables, I don't know why this happened...