Many times calls come into the office from home gardeners who complain that their squash are loaded with blooms, but no fruit are developing. Usually one of two things is not happening. If it is cloudy, or if insecticides are being misused, the bee activity may be absent, so the female flower is not being pollinated. The other thing may be that the flowers present are mostly male flowers, which of course will produce no fruit. If no fruit is being produced, look at these possibilities and take action.
Bees are most active on bright sunny days.
They actually navigate by the sun. They are usually the most active early in the morning and later in the afternoon. Do not spray insecticides during these periods. If there are no bees, it may be that you might have to be a bee for a while and take a small paint brush and transfer pollen from the male flowers to the female flowers. If the lack of bees is not the problem, then look at the flowers to see if any are female.