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