Help With Rotations in MyCareer (RedMC)

I Made a team in my career by replacing players using RedMC. But their roles and minutes get changed as soon as I play a game. I've Changed their contracts in RedMC but it ends up going back. Is there another way to control who is starting? Or is there a way to manipulate the game in to choosing the players I want to start? Why is this only an issue in my career? I feel like I'm missing something. If you understand whats happening please help!

Use the Fantasy Star Trainer for minutes.