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