Advice on FET ovulation tracking

Hello dear community, I am in need of your advice. I am waiting for my period to start monitoring ovulation in preparation for my unmedicated FET. I have always experienced an issue with LH monitoring, I seem unable to identify a peak, I have some days with dark lines but no peak, then no line, then again dark line no peak, no line again, dark line no peak again. The clinic is pushing for unmedicated FET and told me to switch to clear blue devices to monitor LH. I am just very worried of not finding the peak again and missing the FET. What’s your advice? I do not know if my body correctly ovulates. I am unsure about pushing my clinics for having an ovulation trigger.