We are really disappointed with Manchester United's form. Agree with you, they have quality players in their team. I think Manchester United's players are humanly damaged. Each player needs to fulfill their own responsibilities. Also the coach can try some new techniques. Hopefully they will come back in a new way.
There is no need to be disappointed with Manchester United's performance at this time, because it is part of the coach's tactics as well and the stamina that Manchester United must have at this time is very much. Because Manchester United are not only competing in the Europa League, but also in the Premier League, and their players must also keep themselves fit before playing in the 2022 World Cup.