my bread is tough

I make bread every now and then, I made a biga 2 days ago and made bread last night, it was italian bread, it looks good but it was tough, too chewy, especially the rolls. I don't always have this problem, I use a Bosch universal plus to knead. about an hour after it came out of the oven it was fine, but overnight it became tough. I used all purpose unbleached frour. any ideas.

  thanks

    Chet