Product: Madden 18 Platform:Microsoft XBOX One Which console generation do you have? XBOX One S Which mode has this happened in? Franchise Mode Which part of the mode? Offline Summarize your bug...
Go to Owner -> Staff and you can fire/hire staff from here. You will need to chose trainer or scout and use the LT to bring up available staff.
BTW you can do this as many times a season as you want. There is no penalty. Scouting players that you have the corresponding scout for will save you a lot of scouting points.