Got 2 tickets too.
The first time ever I got tickets on presale from this site... after many errors, it gave me a maintenance page "Sorry, high traffic, try again latter" so I hit the previous page button in Chrome, after 2 or 3 min of the high traffic loading page the ticket selection page appeared.
From a friend who tried too with no luck, it seems that if you use the same code in 2 browsers on the same computer, or on 2 devices, at 10am it throws all your connections out of the waiting line and now it seems the code was voided (maybe to prevent people sharing a code?)