I painted my wall with the same colour that it had previously to get rid of some dirt marks however I used an old tub of paint and it left lots of patchiness on the wall. I then sanded the whole wall down and repainted it with brand-new paint and gave it a few coats but the patchiness is still present and I’m not sure why. I didn’t have this problem when I painted the wall a few years ago and don’t have patchiness anywhere else in the room except for on that one wall. Any idea why this is happening?
