@MojangSupport bought the app manecraft I just had to enter a username,now I've been allowed to exchange my computer for a new one because something was wrong. I wanted to log in again, but they're asking to buy the app back now or ask them to give an email and pass word online
Please send us an email at https://help.minecraft.net/hc/en-us/requests/new … and we will assist. Remember to attach your Transaction ID. ^JS