Udayambika some of your problems have to do with different spellings. The other issue you're having has to do with city/state confusion. Urban mapping (Tableau's map provider) thinks that these are the spellings and names of South Korea provinces:
Provinces Busan Daegu Daejeon Gangwon Gwangju Gyeonggi Gyeongsangbuk Gyeongsangnam Jeju Jeollabuk Jeollanam North Chungcheong South Chungcheong Ulsan
Five of the items on your list Urban Mapping has classified as cities.
South Korea.twbx.zip 51.9 KB