Log4OM on import uses "historic data", checking the start/end date of the country to match callsigns in the correct country that existed when the qso was made.
You can import and see YUGOSLAVIA, as example, even if the country doesn't exist anymore, if the QSO matches the date range (and the prefixes) used in Yugo when was an active country.
As far as i can see Chuck the Boss has fixed something in the country file, so update it

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Daniele