Mr Price not helpful

I wanted to pay my Mr Price Money account and because I sometimes shop online and do an EFT I mistakenly transferred money into Mr Price Group's account and after realizing my mistake I called them they asked me to send proof of payment which I did and I was told they would track the payment and it will take 2-3 working days for it to be sorted. It's two weeks now, I have emailed proof of payment 4 times, called the call center 3 times and being told they'll get back to me, I used that chat online and spoke to consultants but my account is still not sorted. What more must I do cause for the bank to reverse the EFT they'll charge me about R300 and they don't guarantee that the money will reverse back into my account and it can take a month also.??