No problem
Firstly I posted the ticket and an email to my bank stating what happened with a screenshot of history (shows confirmation 504 gateway error) and my bank balance/availability.
Didn't get any response till I posted it on their forum (not allowed) and then got some help a few mins later, the day after the request had been sent.
See the rest of the other thread for details
And an hour or so ago, I posted a new thread in their forums about the email being sent and got a response back in my thread a few min later saying that they have contacted the bank and it is up to them now, the money should return within at least 5 or 7 business working days if not ring your bank and tell them to file a chargeback on the first authorisation.
It isn't a transaction payment, it is an authorisation payment.
I ordered it again late last night as deific (no problems that time got the code straight away) said that the pre order bonus was going to end soon (which it didn't

)
So just contact your bank now as well (it is only them really who can fix it) and tell them what happened, see if they can get it sorted for you without involving GMG.