A mole grows inside your skin and if there is a cut then sometimes it is not necessary for mole to disappear. On the other hand if the skin has a cut then the mole can grow over it.
Is It Normal For A Mole To Grow Another Mole On Top Of Itself If It Is Nicked Or Cut?
When you decide to remove a mole and it grows back on the same place it can be that they didn't remove it properly. I would advise you to go back to your doctor.