Photoshop 2020 - An unkown error occured

[CharlieWatt?]

I now get this error about 90% of the time when I'm using photoshop (see attachment below).

When this happens I can no longer use normal functions on the project like 'Save as' and 'copy and paste', as I get the same error with a pop-up saying an unknown error has occurred. So usually my work is lost, unless I leave the project open and try it the next day, it sometimes works... 

It's really frustrating and has wasted a lot of my time.

Photoshop is fully up to date on my PC so I'm not sure what else to do.