I remember reading about this about a year ago, so I'm not sure what the source was and how reliable it was, but I found this meta-analysis of studies researching the effect of the vaccine on people who had previously already received treatment for HPV:
https://pmc.ncbi.nlm.nih.gov/articles/PMC8879645/
This seems to indicate that the vaccine reduces the risk of finding abnormal cells and precancerous lesions for people who already have HPV.
This seems to indicate that the vaccine reduces the risk of finding abnormal cells and precancerous lesions for people who already have HPV.