I sold an item, but there were a lot of problems along the way. I’m Korean. Is there anyone who can help me, please?

No matter the buyer's country, you are dependent on ebay.com customer service, and it is ebay.com's Terms and Conditions that apply. https://www.ebay.com/help/account/contacting-ebay-customer-service/contacter-le-service-clients-ebay?id=4379&st=3&pos=1&query=Contacter%20le%20Service%20clients%20eBay&intent=contacter%20service%20client&lucenceai=lucenceai&docId=HELP1326