Still getting charged after cancelling my subscription

Hi, I have cancelled my VPN subscription 4 months ago, and I’m still getting charged for it. I thought I might haven’t cancelled it but I can’t use VPN on my browser (both desktop and android).
I would like to cancel my paymente and get a refund for the past 4 months I’ve been charged for without being able to use the VPN.
I’m registered with the same email address I registered to the forum.
Thanks ahead, Gal.