Last month I bought a Korail ticket for R/T travel between Seoul and Gyongju for travel on October 1. I will be arriving in Seoul on September 30. The terms and conditions for the ticket sale seem to say that the purchase must be completed some days before I arrive or I risk losing the reservation. Yes, it sounds like I'm saying I only reserved and did not 'purchase', but I did give them my credit card number and there had been a hold put on the CC by Korail.

Has anyone recently bought a Korail ticket in advance and subsequently arrived at or near the day of departure to find that the ticket was still available?
Is there some way or need to more fully complete my purchase?
Thanks in advance.
Peter