How come I am receiving negative ovulation results?

Eliza

This week I am suppose to start ovulation, and I bought three different kinds of ovulation test kits, I got the test strips that have been saying negative for two days now, my clear blue digital that’s negative as well and equate test kit that’s says I’m negative. I’ve ovulated in July and august. I always get my period every month but it’s weird I don’t have any positive ovulation results.