I was just wondering if anybody has used the Clearblue ClearPlan fertility monitor and had it not detect ovulation. The first month I used it, it detected 2 days of peak fertility, and the second month, it didn't detect peak fertility at all, but I did get my period on day 32. I am taking Letrozole to make me ovulate, so I did ovulate since I got a period, but the monitor didn't detect it. Has anyone else had a problem with it? It's supposed to be 99% accurate.