So, that was happening since yesterday, but right now, i restarted my game and loaded that saved game again and now everything is right.
Don't really understand what was the issue, but it's not happening anymore.
Since the update, every new save, i can't change the responsabilities from U-18/U-23 friendlies. Both teams have their respective manager but it comes with me playing by default and i cannot change it.
I can't give the responsability to the respective manager from each team, i can t delegate those responsabilities for them, but it's only with the friendlies. With all other responsabilities i can delegate to whoever i want to.