It seems that Cayan’s site is down, so if you cannot get credit card approvals that is the reason.
Write down the credit card numbers and then get approval when their site comes back up.
As per Cayan:
Cayan’s services are up and running, however, there is a massive DNS outage in the entire east coast. Our ticketing system is also affected by this outage. Unfortunately, there is not much that Cayan can do about this issue. This website lists all the services that are being affected by this outage:
The DNS provider is also providing status updates on the following page:
However, I’ve been calls from shops in California and the mid-west that are also having problems.