AHQ Account Closure

As I read in order to close my account.AHQ , I go to AHQ settings: Close my account and a window opens.

Are you sure you want to close the account? If so, enter your username, then click Close account. After closing the account, you can no longer restore it.

Now at the question Login name I am prompted to enter my login name and close the account.  Then an error window opens ; The username you entered is not the same as the one you usually use to log in.

Is my username the one I use to log in? Or my email address?

I have tried several attempts but always the same thing.And I especially don't want to close my EA account just the AHQ forum.

Can someone help me ?