CD 20 still haven't ovulated

So here's the thing I'm currently on CD 20. Cycles last from 28-34 days normally. I have been using a clear blue digital monitor for 4-5 months and never received a peak. Just lows and highs. I decided this month I was going to do opks the first day I got a high on my monitor. And that was like CD 10. I have not had a positive opk yet. I have been tracking temps taking them at the same time, before eating drinking getting outta bed ect. And my temps are all over the board. I also have not had any ewcm. Any advice?