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