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