hi guys, i tried to change my current username on playroom, but it isn't possible, i have this account already 1 year, and i never changed username, i don't know what is problem now

Can you please explain your issue in more detail?
Is the web interface having issues?
IF so, then what kind?
Do you not know where to go in order to change it?
Have you tried and it hasn't changed?(In which case I suggest you to be patient as helpers are, after all, also humans)
It will be extremely hard to help you out in any way unlesss you're more precise about the exact challenge that you're facing.
Cheers

Think they succeeded as their name was different like an hour ago

everything is ok, has changed after half an hour