if you are a tourist, this will be a torture for you. it doesn't work with Esim, it doesn't work with foreign numbers, ect. I struggled SO much for so long and finally paid for a pass cause I really wanted to bike on my last day along Han river. I got a confirmation email. went back to the bike station and it would not find my pass. I lost over 3 hours in total. crappiest UI design in the world in my opinion. made me lose my precious time on the last day of my trip.
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