Fortnite has anyone else been in my acc?

I had 1,550 V bucks and when I went in the next day there were only 850 v bucks left I think that one of my acquaintances bought what he bought with my v bucks, you happen to know how I can see who what who has given?

Do you play on the console and pc?

Console why? Ps4

So ONLY ps4?

So I also have a laptop fals it works but there it is xD so I PLAY on the Ps4