try either regestering an account and then use it to login
or press quickplay to just start without an account :p
Hmm, if you want to get in contact I could try and help you out over on https://discord.gg/r2aRAgQ
Otherwise you could try-
https://www.newgrounds.com/portal/view/746649
-and see if you have the same problem there.
Good luck ^^