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