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