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