Real Madrid made a mistake by hiring Mbappe and spending too much money for a player like him. Real Madrid had a much better option but Real Madrid couldn't even use the penalty kick they had.
This isn't true completely, Madrid doesn't have mbappe alone as the only player there in their team, they have got some other top good players who are supposed to complement him and he's needing some time to cope completely with Madrid and the Spanish style of football not just the pattern that he's been used to back them in France, moreover he's not acquainted with ancelottis tactical approach just yet so all the blame shouldn't be on mbappes shoulder, some should be shifted to the entire team and Coach.