Superstars but low form

Hi everybody,

I actually have a problem with 3 recruits, top players with high skills and high value but I presume they think they are superstars and don't need to play their game :p
So they get form rating like 4-4-5 ... :mad:

They didn't played any matches for 2 days even a friendly one. Is that the right method ? Should it be more ?
Or do you know another method to increase their forms ?

Thanks in advance for your help

I never really notice form. Maybe it's just because they're so good that they have higher standards for ratings.