korea connectivity k-eta korea 서울 쇼핑 환급 immigration overstay decision Korea korea sim card taxi at night Korea Tax refund in Korea late night bus Korea overstay clearance Korea korea mobile internet 공항 환급 방법 night transportation Korea visa free korea Myeongdong tax kiosk 외국인 택스 리펀 overstay exit risk Korea tourist overstay Korea consequences korea entry requirements tourist exit procedures Korea 한국 세금 환급 esim korea missed last subway Korea Korea tax refund tourist medical emergency Korea VAT refund Korea korea travel tips travel to korea hospital visit tourist Korea tourist exit record Korea korea tourism guide