LinkedIn Korea Seoul Global Center korea employment visa freelance jobs Korea Kowork visa sponsorship Korea job termination Korea foreigner work in South Korea 2025 teaching jobs Korea foreign worker resignation company closed Korea visa foreign worker job change change job korea visa non-teaching jobs Korea fired in Korea visa notice period korea foreign worker ghosted Korea expat career Korea English jobs Korea KOTRA job fair employer shutdown foreign worker Korea Saramin quitting job Korea foreigner foreigner jobs Seoul Korea job search guide unpaid salary Korea foreigner JobKorea Korea job platforms work visa status work visa korea rules part-time jobs Korea employer no response Korea jobs in Korea for foreigners resigning job korea XpatJobs work visa korea