Unhappy Customer 😭😭

I called DSTV to cancel my subscription in 2022 and requested them to refund me back my balance which was paid in advance. I have been send from pillar to post to date no money is refunded, instead now I was told that I will be investigated to proof that I had paid the money. Then I was told to send bank statement and proof of account, next thing they want a actual payment that was done to DSTV account. Irrespective of explanation that I do not have that anymore since the beneficiary was deleted. I am so frustrated I don't know how to get my refund back.