When I opened it I found a mostly-completed puzzle (race car image) which I could make some progress on, but I also found at least 3 pieces which were exact dup

When I opened it I found a mostly-completed puzzle (race car image) which I could make some progress on, but I also found at least 3 pieces which were exact duplicates of each other — one in the right place and locked, and one movable but obviously identical to the locked piece. I'm also pretty sure that there were some places whose fitting piece wasn't on the board at all. If this isn't on purpose as chaff, then the puzzle is unsolvable due to this bug.