Refund for undelivered goods from Fair Price Factory Shop

Good Day

My problem today is about the factory shop that sells decorating goods. Between me and the company I ordered good sin June and and paid for the goods. later I discoverd that i needed to pay for insurance which they said to me it was R1000 which I did pay then they later said I should pay R200 because it has increased to R1200. Then I kept on paying until the insurance money was R2000. In July when I contacted them about my goods I was told that the insurance for those good is R2980 and they can see i have aleady paid R2000 and need to add R980 so that I can get my goods. Lately when I asked them about my goods they are now telling me that I'm R1000 short for the isurance and I have forwarded my proof of payment to show that I paid everything and has nothing outstanding and the are still refusing to deliver or payback my money. I don't know what to do anymore and they told me even if I write to HELLOPETER it will be of no use. I fail to understand the missing R1000 that they are talking about since I have proof that I made all payments for the Insurance so that I can get my goods

Your help will be highly appriciated. Kind Regards Nneheng Modise