Prepared statement does not match bind variables even tho it do? : As far as i can tell i select 6 columns from the table, and i bind 6 variables so why does it tell me that it does not match?

This is for a rating script where people can vote cars

This script works with the Insert/Select/Union but i noticed that everything was getting really slow when people voted the images from the folder structure so i would like to move the selected images to another folder where they can be accessed faster but i seem to get a problem when trying to bind the result, this is usually not a problem for me, could someone explain to me why this is happening in this particular case ?

    $stmt = $dbCon->prepare(" INSERT INTO cars_daily ( cars_daily_identifier, cars_daily_source, cars_daily_views, cars_daily_votes, cars_daily_rating, cars_daily_category) "
            . " (SELECT cars_car_id, cars_car_source, cars_car_views, cars_car_votes, cars_car_rating, cars_car_category "
            . " FROM cars_bcar "
            . " WHERE cars_car_category IN (?) ORDER BY RAND() LIMIT 5) "
            . " UNION "
            . " (SELECT cars_car_id, cars_car_source, cars_car_views, cars_car_votes, cars_car_rating, cars_car_category "
            . " FROM cars_car "
            . " WHERE cars_car_category IN (?) ORDER BY RAND() LIMIT 5) "
            . " UNION "
            . " (SELECT cars_car_id, cars_car_source, cars_car_views, cars_car_votes, cars_car_rating, cars_car_category "
            . " FROM cars_car "
            . " WHERE cars_car_category IN (?) ORDER BY RAND() LIMIT 5) ");
    $stmt->bind_param('iii', $cat1, $cat2, $cat3);
    if ($stmt->execute()) {
        echo "<br><br>";
        echo "Success SELECT/INSERT";
        echo "<br><br>";
    } else {
        echo "<br><br>";
        print_r($stmt->error);
        echo "<br><br>";
        echo "Fail SELECT/INSERT";
    }
    
            $stmt->bind_result($cars_car_id, $cars_cars_source, $cars_car_views, $cars_car_votes, $cars_car_rating, $cars_car_category);
            while ($stmt->fetch()) {
    
                copy("models/$cars_cars_source", "daily/$cars_cars_source");
            }