Wrong billing

My name Ntombi Ngobese. I had a car insurance policy with AIG. In January 2021 on the 04th I added a second car to the insurance. My policy number is AIG-01655-DA. The payment for the first car was deducted on the 4th (amount R1148. 23).The payment for the added car went through on the 5th of January 2021 (amount R1223. 91). I then realized that the access for the new car was saying 5% of the cost then I decided to look for another insurance immidiately and request termination of the second car to affected end of Jan. They told me they will only send cancelation confirmation at the end of January because their system works different. When I send the insurance documents to the bank we noticed there was an error. When I call to request the documents I found that my car was no longer covered. They ask to reload my information in order to print the documents. On the 18th of January I saw a deduction of R836. 96 called pro-rata. I phoned them and they told me finance will correct and refund my money. In February they deducted R1758. 71, I called and they asked me to send documents to prove I have another insurance for the same car. I did that, but they continued deducting R2552. 33 everymonth until May. I keep on phoning and being transferred from one person to another and requested to send the same documents over and over again. They owe me a refund of R5659. 74. Since their insurance is closed, the people who answer the phone does not even speak proper English. You hold for a very long time before anyone can attend to your calls. I don't know what to do anymore, but I want my money back.