Refund (Bad service) online purchase

I have place an order on Mrp app and it was cancelled and I reorder those items and add two more

There was a difference in price and I had to pay the difference and my order was cancelled again but I have already made the payment on my bank app

Reorder those dress and I had to pay the difference for the second time

I have called Mrp's customer service using my own airtime and I was told the first payment was abandoned by Mrp it in my bank of which that didn't happen.

I have the call center more than 38 times and I was told to email proof of payment and my bank statement of which I have done and when I called the following day I was told that refund was done I must check with my bank

I kept on telling them that I didn't receive my money and the last person I spoke to told me that refund was done and there is nothing wmhe can do

My question to him was when was it done and he said it was on the 28th of December at 18:12

I told him it impossible because payment was only done around 18:18

I want Mrprice to refund me my money and their customer assistance must stop treating us like fools or we know nothing