The BUD-CDG segment is operated by AF, presumably? You say "codeshare", but are you flying under the DL flight number (if any) or are you flying under an AF flight number, but ticketed on DL stock.

Do "view receipt" on the DL itinerary. Make sure that the receipt properly shows the BUD-CDG segment and that there is no misalignment with the ticket and the flight as shown on the AF website.