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