The ovulation strips test to see if your body has given the chemical command to your ovary to grow and release an egg. They do NOT test to see if you actually did grow and release an egg: the only way to check that is through ultrasound scans (or surgery).
So your body may be trying to ovulate, but not actually ovulating, in which case the drug clomid can help.
Even if you are ovulating, the egg may be no good. You released your best eggs when you were around age 14: the body does the best ones first (according to my doctor at London’s top IVF clinic). By the time a woman is in her thirties she’s working with the dregs, to be blunt.
Even if you did ovulate, and the egg was good, it won’t necessarily fertilise: perhaps your tubes have scarring from an infection or are in a tangle that narrows the tubes and the sperm simply can’t reach the egg.
Even if the sperm does get to the egg, it may be shit sperm and the fertilised egg dies before you ever knew it existed.
Even if you did ovulate, and the egg was good, and good sperm manages to reach it and fertilise it, it might not successfully implant into your womb. Perhaps a polyp or scar tissue from a previous pregnancy gets in the way, or perhaps your lining has some other issue.
Get top medical advice asap is my advice to you and don’t listen to the idiots telling you ‘just relax / go on holiday / have acupuncture.’ You have a medical issue, the doctors may or may not be able to identify it and help.
IVF didn’t work for me as my body was simply not willing to grow good eggs or allow them to implant. I sincerely wish you better luck.