MY USERNAME DOES NOT WORK ANYMORE

I cant log into my account anymore, without requesting new login data. I am sure my password is correct.

Please remember, your username is not your e-mail address. You chose your username yourself upon creation of your user account. 

You can see your username , when clicking the link in the mail you received after requesting new login data. On the top right of the page you will see "welcome" followed by your username.