It sounds like they are not getting pollinated. They require bee pollination to mature.

May want to try your luck at hand pollinating.

Even all female varieties moderate their fruit set. Frequently the first flowers do not set fruit, but things pick up when the second and third set of branches come into bloom. The plants are probably setting fruit now.

No pollination:
It can be due to : No insects (bees ) AND?OR no male flowers around.

Should I thin them out? Maybe they are planted to thick and the flowers are not seen or sought out because they are hidden under so much foliage......?

And hand pollination....I guess swirling a qtip around in each flower would get the job done, no?

yes, so long as you do it in the male first. I use a small paint brush.