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