Do you know how foreigners can send money through Woori SIM Bank in Korea?

Hello! I'm a foreigner who has been in Korea for about 6 months. I'm trying to purchase a Woori prepaid SIM card online in Itaewon, but I got a bit confused because the price is different in KRW and USD. They said it's because of the exchange rate. Even though they said it's okay to pay in Korean won, I tried to pay with my credit card, but it seems that Korean cards don't work for foreigners like me. They suggested doing a bank transfer, but it's my first time and I'm a bit flustered. I received the order confirmation via email and also got instructions for payment, but I'm not sure how to do the transfer. Does anyone have a similar experience? Any advice would be greatly appreciated! Thank you so much!