Autoglym interior shampoo can be sprayed on directly and wiped with a microfibres cloth. Autoglym also do a high foam interior cleaner that might be worth a look, in combination with a soft bristled brush (detailing brush, not a nail brush).
You could also try differing dilutions of all purpose cleaner, start at 1:10, them work up to 1:5 or 1:1 (50% strength) if necessary. Ensure it’s a mild cleaner without bleach ! Elbow grease brand from Poundland is worth a try, but the usual household brands such as Flash work well too.