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