My tomato plants have lots of blossoms but aren't fruiting
There are lots of environmental and cultural factors that could result in flowers but no fruit. Excessive heat kills the pollen of tomato flowers. Excessive rain can hamper the pollination process. Excessive nitrogen fertilizer can result in excessive foliage and not much fruit. Also, the extended cool spring weather we experienced set everything back at least two weeks this year, so it may be that patience is the best advice for now. Incidentally, you're in good company. This is a common complaint this year.
Thank you. Your advice was helpful.