A coverup tattoo is not about putting a fresh layer of ink over an
old tattoo and making it disappear like paint on a wall. Tattoo pigment does not work like that.
What a good tattoo cover-up actually does is obscure, camouflage, and break up the old tattoo so your eye reads the new design instead of the old one. That is a big difference, and it is why cover-up tattoos take planning.