What is the most common tech mistake you see people make repeatedly that's an easy fix once you know it

[HiggsField41]

Force closing every app constantly thinking it saves battery, when on modern phones it actually makes battery life worse by forcing apps to fully reload from scratch

[Ria99]

Never actually restarting devices regularly, a huge number of reported glitches resolve with a simple restart that people skip in favor of more complicated troubleshooting first