Clear blue fertility help

I bought the clear blue ovulation machine and am using it for the first time this month. According to my apps and I have been having symptoms I should be ovulating today. Well my clear blue machine is saying I'm low fertitily. So I tested with a strip and the strip implies I'm ovulating. I thought the machine was #1 for detecting high fertitily days? How is it not detecting anything but the cheapo strip I have did? Anyone can help?