It's not a fault with the game, it is just your failure to react to how the opposition changes. I used to have the same problem when I didn't take notice of how my tactics work etc.
I used to watch my games on ultra fast and only key moments being shown, this meant I missed when it says that, for example, Man United have converted to an attacking style. Now when I see that, I look to counter the change that they made, be it going more defensively and trying to counter or just trying to utilize how their fullbacks and midfielders being out of position and high up the park.
This FM is much harder than all the rest as it is far more realistic and the AI seems much more intelligent than in previous years, this FM really outlines the better managers within the community.