I am trying to buy a plane ticket for my son to fly from Tokyo to Seoul.

I tried doing it on expedia and I kept getting a message that it would not go through and I needed to talk to my card provider. I contacted the card provider and they said they didn't see any transactions and hadn't declined any.

So I tried going to Capital One travel, got all the way to the end, the transaction would not go through.

Any idea what is going on?

He is an authorized user on my card, with his own card, and tried getting the ticket himself - the same thing happened. But Capital One says there is nothing wrong.

https://www.koreanair.com/

What is the date of travel? One-way or roundtrip?
What fare did you see?
Is he in Japan?

There are several carriers serving those cities. Search using TYO (for Haneda and Narita) and SEL (for Seoul Gimpo and Inchon). Best fares look to be from NRT to ICN.

Try booking here: ZIPAIR Official Website

Also, try booking via Amex Travel. That is what I had to do to buy a ticket from Asiana.

Fare should be about $250 for a roundtrip for an advance purchase.

Thanks so much. Yes, he's in Japan. I had looked at Korean Air but almost all the flights are full on the day he needs to return. I hadn't even heard of ZipAir! There are so many carriers. Appreciate it!

What dates?
He could probably get a ticket from a TA at a train station.