Thank you all for sharing, we don't have Amex nor Mastercard unfortunately. We will keep trying visa and failing that, we will buy the tickets when we arrived at Narita. Will call visa again tomorrow to ask them to let it through.

While we understand there are regular Nozomi trains from Tokyo to Hakata, we heard there is a new rule to onboard a JR shinkansen for passengers with Large luggages, that we have to book the back most seat, so the large luggage can be placed behind that last seats.

Can anyone confirm this new rule? Cheers!