Glitch hits Olympic ticket sales
Ticket sales for the Olympics hit a glitch just hours after sales began on Tuesday.
Sports fans with Visa cards which expire before the end of August found the website could not process their orders.
Visa is the only way to pay online for the 6.6 million tickets. There is a six week period to April 26 at 11.59pm to apply.
A London 2012 spokesman said: "What Visa is trying to do is to ensure that more people will be able to apply by bringing this threshold forward so that it will only be if your card expires before the end of June that the site will not process your order.
"It means if your card runs out in July you will still be able to apply, but you will just need to come into the process a bit later."
London 2012 said these buyers could still make their choices of the events they want to see but cannot currently finish the process on the system.
A spokesman said: "It is being sorted. It is an issue with Visa rather than the website or our systems."
He added there is nothing wrong with the site and the chance of getting a ticket is not lost provided applications are made before the deadline.
The expiry dates are noted on the system but the problem became clear after people started to apply.
There has been a steady stream of application since tickets went on sale at midnight, he added. Payments are not taken on successful applications until around June.