Inadequate Biopsy again!

Hello
I am hoping someone on here has had similar experience with biopsies.
My smear came back abnormal and at the end of September I had a Colposcopy appointment and two biopsies were taken. These came back inadequate and then I had another two biopsies taken a few weeks ago and now these have come back as inadequate. Both biopsies showed positive for HPV and during the Colposcopy the nurse explained that she could definitely see that I had high grade cell changes when she used the dye to show the changed cells.
I am due another appointment on 8 Dec at Gynaecology.
I am confused and anxious at the same time. I explained to my GP that for a few years I’ve had some pelvic pain, very heavy periods and constant discharge. She suggested Endometriosis but I’ve had a scan to prove otherwise.
I just need to know if inadequate biopsies are a sign nothing is wrong or has anyone had this experience and what happened? Thank you…X