It seems like the Korean CD store leesmusic recently recently abandoned their domain in favor of a new "Naver Smartstore" site: https://m.smartstore.naver.com/leesmusic/
As the link format they use is incompatible with the old one (different inventory/IDs), the previous links should be marked as ended.
Example release with such an URL: https://musicbrainz.org/release/8efd324f-dbd1-4cf7-a212-ef1d05864704