Requesting for a refund

Good afternoon. I have a complaint. A few weeks back my mom was paying DSTV but mistakenly pressed DSV. She paid DSV. So I called the company and I explained everything, they said I should send the bank letter and the proof of payment. I did that, and we were requesting a refund. It has been weeks now they haven't gotten back to us. The lady who helped us first was Onelenna and then Tryphina. I sent them emails again to check how far, but they didn't respond. My number is +***. Thank you