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