If you change your in-game name for Minecraft, Towny counts you as a new player. Numerous of people (including someone in my town) are basically removed from the town because they changed their name. If you then add this player again, you will have the same person added twice, also counting as two different persons. I think this could easily be abused and should be fixed as soon as possible. Moreover, if the mayor changes his/her in-game name, they would lose their town permissions with their new name. (Something that happened to Cmoreno32, who is or more like WAS the owner of the town Triggered) Spoiler: Dark_Wolf600 counting as two persons in my town The 9th and last person is the same person.
There really is nothing we can do about this, it is something players need to bare in mind when changing their names, Unfortuneatly the only people with the perms to fix this are Noob and Cyp.