My name doesnt change

so i was playing miniblox with my sister (AvaStar) and she helped me change my name to (ILoveYou) but the next day when i logged on again it said my name was FreezyHotdog. some randome numbers so she said its just a but chagne it again and then it said you have to wait 25 days to change your name and im like THIS NAME IS UGLY i want a good name please give me back my name if you stole it -AvaStar's sister IM MAD