Glaring continuity error!

Apart from the fact that Mark Lester, at 18, is far too old to play the pre-teen title characters, there is also a glaring error regarding the hair styles of the protagonists. When they meet, the pauper Tom Canty has a huge, Afro hair style, while Prince Edward has a quaint little page boy hair style, curled under at the edges. But when they exchange clothes, the prince now has the Afro hair style and the pauper now has the page boy hair style. Surely, it should have been the other way round, or, better still, they should both have had the same hair style. Somebody goofed on that one!