Dstv wont refund wrongful debit

I cancelled all subscriptions to my late husbands account on 7 Dec 21 via the app. I took a screenshot confirming subscriptions are cancelled with I have emailed 4 times as you do not recieve confirmation or feedback after cancelling. My account was still debited in January 2022. I am an unemployed widow with two children and can not afford the subscription. WHICH IS WHY I CANCELLES IT. I have had numerous emails and telephone conversations. They maintain I only cancelled showmax?? The decoder has been unplugged since the beginning of December 2021. So now it's my word against their system. Dstv are refusing to refund my money debited wrongfully in January 2022. What a disgrace this company is !!!! So unfair.