I think Bayer Leverkusen wants to send Wirtz to another team. Because they will be in the Champions League next year and they also want to be champions in the Bundesliga. Their biggest rival in the Bundesliga is of course Bayern Munich. They don't want Bayern Munich to get stronger, so they offer them a different price. In my opinion, this is a situation that arises from the competition between the clubs. It is normal for such things to happen in football because you don't want your strongest rival to get stronger and you don't want them to get stronger by taking your best player.