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