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