Horizontal lines on MacBook Air 2020 Screen

Recently I've been having issues with my MacBook Air 2020 i5 screen. There are flickering horizontal lines on the display, usually when I haven't used the laptop in a few hours. I think they are caused by the low temperature in my flat/outside, as when I go into the library or lecture theatres which are warmer, the problem resolves quickly. I also don't have any issues when I go back to my family home (which has the heating on all the time). I took it to the Apple store to get it checked over and they said there was no internal problems or connector issues, and it would probably be the screen, but they weren't sure because the screen wasn't acting up at that time (conveniently!). I've always taken great care of my laptop (never dropped, no cracks, etc.) so I'm unsure how this problem would've come about.

Has anyone else experienced something similar? It's not a big enough issue for me to spend money on a screen replacement or new laptop, but it is really annoying when I'm trying to get work done in my uni flat!