Keyboard and track pad freeze

I have a 2011 MacBook Air A1370, with a keyboard and track pad issue. The keyboard and track pad freeze whenever I try to use them no matter what I'm doing, even during startup, making the laptop completely unusable. However when I plug in an external keyboard and mouse (both bluetooth) I'm able to use the laptop completely fine with no issues at all. Or when I hold the laptop at a certain angle/tilt then it works fine as well.

Not entirely sure what may be the cause of this issue and I'm all out of ideas. I've tried a factory reset (laptop runs on High Sierra), and that fixes it but temporarily; usually after a restart the problem comes back. I'm not too familiar with MacBooks so my technical skills here are completely fried. If anyone has any ideas or requires more detail to help out don't hesitate, I really need the help, I'd like to give this laptop to my nephew for school as I have no use for it.