In your panel take a look at the main menu on the left. Right down the bottom is a Support menu. Just click on that then click ‘Contact Support’. The first thing you’ll notice is an announcement regarding mail, but if you don’t think the notice pertains to your problem you can elect to submit a ticket by ticking “Email” in Step 1 and continuing on through the steps to submit a support ticket.
When submitting a ticket, give as much information as possible (not a@abc b@abc) that concerns your issue and try to keep it clear, concise, and to the point. That way Support are better able to ascertain if your problem is account-based more quickly.