With clubs heavily into the registratuion process for Summer her are some user tips.

When registering this season returning members are asked to use the same login details as previously, even when changing clubs. Every time you login as a new member or use a different email it creates a duplicate entry which stays in the system forever.
Like me if you have stuffed up and have more than 1 profile/Fiba member number always use the same one (the top one). Your payment transaction history is linked to these member numbers so if you keep using different logins the system thinks you haven't paid and will OVER CHARGE you.
If you can't remember the email address you used, contact your club they can get that info for you.