Ovulation sticks

So I have been doing ovulation sticks everyday apart from when I am on my period and I never within a few months have had a positive. I did some blood test with gp on cycle day 21 and cycle day 3 and they confirmed I am fine and healthy with fsh/ovulation. So I dont understand why I'm not getting a positive ovulation test ( I test twice a day). I never even have ewcm. I'm a freak that's all i am