What tests do you use ?
I used to use some cheap ones off amazon and never got a positive ovulation as soon as I switched over I did
What tests do you use and how often are you testing
You could have a very short surge which is the case for a lot of women meaning you may only get a positive/peak result for only a couple hours rather than it being positive for 24 hours etc. It could just be a simple case of just missing it due to it happening so quickly, if this is the case for you I would test several times a day - at least 3 times a day to try and catch it x
I did this for a while and I was testing twice a day morning 10am and evening 6pm. I forgot to test the one day and ended up testing at midnight and it was positive but when I tested the next morning it was negative. So it’s possible you are missing your surge and it’s a very short one.
If it helps, I was using first urine of the day for a few months and didn't get a positive, once I tested at 10 am each day I did. There have been some exceptions where I haven't had a positive and I think I've missed a short surge as the others have suggested
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