No line on OPK???

Sierra

I’ve been using OPK for a few months now. They’ve been working pretty well. My periods aren’t super consistent, between 25-27 days. But what IS consistent is that I get my period 14 days after I get a positive LH. Last month is did not get a positive-I got close and then suddenly the test line disappeared, which was weird but I got my period 14 days from when it was “close” so I thought I just missed it. This month I’m on CD 11 and I’m still getting NO LINES. Has this happened to anyone else? All strips are from the same kit.

Here are my strips from a couple months back and this month for comparison