Vodafone's Refusal to Cancel My GSM Line and Ongoing Bill Payments

Vodafone refuses to cancel my GSM line despite numerous requests. I've been trying to cancel since 13/09/2022 at 16:09, but they still charge me every month. They told me months ago that I would get my money back for payments I made to Vodafone Debt Collection, so I gave them my IBAN. But not only did I not get any money back, but the bills keep coming every month. Customer service is a total mess; everyone tells me different things and sends me to departments that don't help. I've been a customer for years and have several lines, but I'm moving them all to a different company. I want to cancel line number 544...1409 right away and get my money back for the last 10 months.