My holly bush flowered but when the buds appeared they all fell of
Certified GKH Gardening Expert
Can you include a photo? Has this ever had berries before? If not, then you could very well have a male bush. They will flower but not produce berries. It is necessary to have, both, a male and a female nearby to produce berries.
Alternatively, if there are not any other hollies nearby, which is unlikely but can happen, then there is a chance that it could be female but not getting pollinated.