Currys PC World

I never sign into insurances or technical support additional fees. Never that is my way which I never take. I discovered by accident that since 2014 ( we have 2019) Curries charges me randomly, usually 3 times a month £6.50 & £8 for Product Support which I never took. I discovered that 2019 they started charge me 3 times a month, 2018 they were taking twice a month, and one month 2018 has been skipped probably and they charged me nothing, however all months before they were chagrinning me randomly £6.50 & £8 twice o three times a month. I went to the stores and have been told that they no nothing about that but if I wish they can cancel this from next week. They have no proof that I sign for any Product Support because I never did. I would like to get all my money back. Please advise what shall I do? It wasn't direct debit set, it was always snick standard random inconsistent payment.