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