OPKs not working for me 😩

Does anyone else find that OPKs dont work for you but know that you are in fact ovulating😳? I used them once before for an entire month and never got a postive ➕ and I actually concieved that month with my 👶son. However that was 5 years ago & I am having the same issue again now. Any suggestions? This is getting frustrating. I use the strips by the way. Thanks! 😊