I just encountered a similar issue 1 week ago with my UOB CC.

Luckily I noted down the Booking reference and had screenshots.

I emailed them and the got back to me to sort it out.

But your seats are being held for 72 hours, after that if its not ticketed, teh booking gets cancelled and the seats may / may not be release back to inventory.

Fastest way is still to call them.