Why isn't my touch screen working after it overheated

Story: Back a few years ago, this phone overheated from using the wifi hotspot feature for too long. When the phone turned back on, the touch screen refused to work, so my dad brought it to a repair shop, turns out they can't really do anything, which I have a hard time believing but there's only 1 actually good repair shop where I live. In a last ditch effort, I plugged in a mouse to the phone, backed up all the files and factory reset it, turns out, that didn't do crap and I can't use a mouse in the setup screen. TL:DR: A few years ago Samsung a50 overheated and now touch doesn't work; brought it to the only repair shop in town and couldn't do anything.

What I have tried already from talking to someone online: Putting in a sim card into the slot, firmly pressing where ever I can (still trying that) and that's pretty much it.

Closing: I do not want to open the phone because I don't have the tools for that and I am scared that I will break the phone. I have a Windows 11 PC at hand anytime if that would help. There's also a rattling in the bottom left corner but from research it should mean much.