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