two roosters, one not doing the job.

If he isn't crowing and isn't getting involved he may not be mature. Or your roo just wont let him because, he has more dominance and can easily over power him. Argo he isn't' allowed to mate, I would give it time

 

The roo that isn't mating with the hens is being supressed by the dominant alpha roo, he dare not mate the hens in the alpha's presense.

 

How long have you had him? Chickens need some time to settle into a new home.
Also, often times only the alpha rooster is doing the majority of the mating, crowing, tending to the girls.
The subordinate roosters try but depending on how fearful or submissive they are of the alpha, they may only try to mate, crow, care for the girls when he's not around.

 

Get a little more agressive roo he will have the guts to get involved. It worked for me.

 

you could confine the dominant rooster for a few days and see if that helps the new rooster get any braver. But, if he is real young the hens will know and may not not allow him to mate with them until he is older.