dave is the cannon name and can't be changed that moment at the start is just for easter eggs
No, it's not wrong. A few updates back a change was made to the earlier days where that was edited (I think it was 5 updates ago?). But because I knew a bunch of people had old saves, I've been supporting that in-code so it's not strange. Any new saves you'll be forced into having "Dave", but if you have old ones you'll be able to use the name you picked then.