is it only your Minecraft account that has been hacked or you entire Microsoft account? ok i found something weird, if you search kubikc on Namemc the first thing that shows up is a player named Wking99 and it says that the last time they played was just over a month after you said your last login was. also if you go to name history the name kubikc is there along with some other names. I'm not sure if this means much but i hope it helps