Probably one of the game files is either "corrupted" or "not up to date". Re-installing the game using their latest setup usually fixes the issue.
I get this error when I trying to update my MapleSEA version from v131 to v131.2 using manual patch
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Probably one of the game files is either "corrupted" or "not up to date". Re-installing the game using their latest setup usually fixes the issue.