Q.crooked neck squash
Why are they rotting and falling off at around 1 inch long? They have about 20 blooms on them at one time?

There are a number of diseases that can cause the squash to rot on the vines.
A bit more investigation and looking for signs that help identify the fungus or bacteria will dictate treatment or how to correct.
The links below will help you.
https://www.gardeningknowhow.com/edible/vegetables/squash/squash-pumpkin-rot-disease.htm
https://www.gardeningknowhow.com/edible/vegetables/squash/tips-for-growing-squash.htm
https://www.gardeningknowhow.com/edible/vegetables/squash/squash-blossoms-falling-off-vine.htm
https://www.gardeningknowhow.com/edible/vegetables/squash/pollinate-squash-by-hand.htm