Why does my switch error and crash when idle?

I’ve had my switch around 2 or so years. It’s a V2 model (HAC-001 (-01)). However within the past few months, if i go AFK on a game for too long, leave it on the home screen too long or just leave it completely on and idle in any way, it will eventually freeze and throw up an error. The error code is 2168-0002, which i’ve heard is normally caused by a hardware issue. I’ve made sure the Switch is fully updated, and it runs fine so long as i continue playing it. Any reasons why it does this? Is it something that can easily be fixed with a repair?