I use fill commands to test things out in my creative world. But after this most recent update, It says syntax error: unexpected "playername". Is this intentional? If so how do I use fill commands now ???

Example of what I type in a command block/ execute noxmiles ~~~ fill ~30 ~20 ~30 ~~~ air

Excepted result/ Replace blocks

Observed Results/ My player name isn't correct it says syntax error unexpected noxmiles at execute 

I've tried both my playstation username and Microsoft account username But it says the same thing.