After pressing play button, creating a new class defaults to Engine folder

I think this is happening after I try my code by pressing the play in the engine (code compiles and works) but after that, I’m no longer able to create new classes in the source folder! The UI wants me to create them in the Engine/Binaries/Win64 folder. I’ve tried redoing the whole project twice now and something triggers that and I’m stumped.

If I try to point to the source folder this is the error I see: