Hi . Does anyone know why wind 11 defender stops midway during a full scan?

Microsoft suggested reinstalling the os but it is the same either way.

I reinstalled win 11 with the iso from microsoft’s official website.

it just stopped right now at around 2:30 but the scan result says it finished about an hour ago, which wasnt true.

I have tested my RAM with memtest (ycruncher etc… loads of them in extreme settings) extensively and there was no sign of error in a thorough test lasting for 2 hours crunching difficult mathematical numbers.

I have no idea what is causing this. this happens to my older laptop unit that got replaced, which was of the exactly same model as this one too.