What the actual heck does an NGA grade even mean?

I have an NGA mark for SOC201 and by doing some research found out it means "no grade available"... is this something to do with quercus being down? I'm so lost. I also read on some reddit posts that it also can mean you are being investigated for an academic offence which i'm also confused about because i had gotten all my grades back except for my final online exam which i did not plagiarize or use any AI for.

Does anyone know what NGA can mean or have that showing up for them too?