Pollination of Atemoya

I post a question but not sure how to get answers so I’ll repeat my questions here.
I hand pollinate my atemoya successfully and enjoy luscious fruits every year, Last years pollination yielded to many golf ball size fruits that are hard and even turned black and inedible ones.
Question
!. What happened, why?
2.can I use pollens from flowers that are pollinated and has turned in male stage?
Any helpful reply is most appreciated. Thank you!

Hi Cora, It must be discouraging to see that happen because a good atemoya is delicious. It is very hard to diagnose such a problem; it could be caused by poor pollination, by too much or too little water or plant nutrients, or by pests of some sort. I understand that you are already hand pollinating but perhaps this one article on hand pollination that ECHO published a few years ago may have some new information for you – http://edn.link/7ymjk6