I would like to cancel the subscription and get my money back. A purchase worth 93 euros has been made on 31/10/24 automatically, which I do not want because I have purchased a protective program of yours with another email
You need to cancel to prevent automatic renewal - Cancelling automatic renewal of the Avast subscription - See https://support.avast.com/en-en/article/35.
There is other advice on that page.
It isn’t wise to post your email address on a publicly available web forum. That said I don’t think you can edit your post - I will try to draw attention to it.