Ovulation one cycle then not the next??

Mikaela

I took 100mg days 5-9 last cycle and ovulated and even got a period from it. This cycle I did it again 100mg days 5-9 and the progesterone levels were only .05 so I definitely didn't ovulate. How is it that it worked and then didn't? Has this happened to anyone? This is my third cycle so I'm not sure what the doctor will do next. She originally only wanted to do three cycles so idk if I will get to do anymore 😔