Starting
January 1, 2019, if you entered the wrong metro platform, you can get out by
scanning your card on the wrong fare gate and then re-enter the correct fare
gate within five minutes in the same station without any additional charges. You
don’t need to call a conductor for help or repay the fare.
It
is only applicable when paying the fare by credit card, prepaid transportation
card or season ticket (1-day, 7-day, 1-month pass).
Website:
https://www.humetro.busan.kr/