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