|I had berries on my holly bush once, the nursery that planted them indicated they were male and female, could the soil be lacking something?
|Holly (Ilex) have separate male and female plants that must be reasonably close to one another for insects to transfer pollen so the flowers on the female plants will produce berries. If your plants had berries once, they'll have them again. Sometimes it takes a while for plants to become established before they can perform as expected. Make sure your plants get summer water and don't prune them, (except lightly to shape them). Don't fertilize at this time, and just take a wait and see attitude. The female plants will produce berries when they're ready.