Causes of cervical dysplasia that are not HPV

I'm 30F, have been dealing with abnormal smears for about 4 years now. I get colposcopies every 6-12 months, and my last one, there were no cell changes which is great/very reassuring! But I've cycled between CIN1 and CIN2 before in the last few years so I'm still always cautious that it may come back.

I'm a bit of an unusual case in that I don't have HPV. I got the vaccine at 13 and have only had one sexual partner/long-term monogamous relationship, so I've never contracted it. The cervical cancer screening program in my country works by looking for HPV in smears, then anyone who has it, their sample is further tested. Because I'll never test positive for HPV, I need to be more vigilant than just going for the national screening program.

I'm wondering if anyone is in the same position as me, in that they have cervical cell changes that aren't caused by HPV. What are some other causes? I've read that cervical inflammation can be a cause but not sure how that occurs. I just want to be aware so I can maybe mitigate the causes and keep myself safe in future. Thanks in advance!