I tried forum search, but nothing came up.

I booked a ticket (with EY) months ago, then had to rebook recently (with a different card) and shortly after got this email:

"We were unable to authenticate the payment details of your booking; therefore your ticket has been suspended on security grounds."

The booking reference on their website still shows as "confirmed" though.

Both payments cleared.

They said I'd have to bring the card with me when checking in for the flight. But which one? Due to the timing of the suspension, I suspect there was a problem with the verification of the second card (used for rebooking fee), not for the first card (used for initial booking).

What happens if I do not show up to the flight? Does this situation give me the opportunity to no-show without penalty?

have you called them?

Bring both cards with you?

Somehow I doubt no-showing will create an automatic refund.

Straighten this out NOW! You probably have a confirmed reservation but no ticket.

Do what you can to get this resolved before you show up for the flight. Call them to see what you need to do if you have not done so already, and then see if you can do it before the flight. It may be as simple as showing the card at the ticket counter, or it may be much more complicated.

The last thing you want to do is just show up and hope for the best.

I have called them several times. All they tell me is to bring my card with me.

I just checked etihad.com, I apparently do have a ticket number:

Issuing Airline: EY
Ticket status: e-ticket processed 27SEP12
e-ticket number: 607-2108393373-74
Tour code: *WEB

So no-show doesn't help? I didn't get a Tibet permit, which makes the whole trip obsolete.

A 'no show' will not help: you have already paid for, and been issued a ticket.