student attendance Korea international student visa rejection Korea international student administrative risk Korea student visa attendance rules Korea student visa transfer Korea international student immigration review Korea study in Korea job seeking visa korea D-2 visa Korea student visa after graduation student visa Korea part-time work Korea student visa document mistake Korea hikorea d10 student work permit Korea student visa instability Korea student visa korea rules international student korea immigration attendance korea student visa korea attendance work rules international student korea immigration student part time work korea visa student visa pattern issues Korea international student job rules korea university change immigration Korea D-2 part-time job international student visa korea problems student visa korea attendance rules Korean university visa d-10 visa korea international student attendance Korea part-time work Korea international students D-4 work permission international student Korea