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