When should I NOT be using OPKs?

Kate • 30, Gwendolyn Rae 4/2/18; Aurora Rita 5/23/20

Hello,

I've been TTC for 10 months now. In June I began temping and using OPKs. I was unsure of when i actually ovulated. I thought i ovulated June 19 but then I used an OPK a few days later & it was still semi dark.

I could really use some clarification and help on when I should stop using the OPK. I purchased a digital one so I will have a YES instead of my worrying brain.