Refusing to refund my money

Around October 2021, bought a laptop at Exact in Vaal Mall Vanderbijlpark. I took their in-store insurance. They charged me double insurance fees for 10 months. When I enquired, they said it was a mistake and they promised to refund me R710.00. Instead, they refunded me R7,10 in July 2022. I followed up on the matter but they never send my money back. They always give me different reference numbers and respond with a message "Your matter has been resolved" without refunding me. I do no longer want the remaining balance, I want their insurance canceled and all of my money returned from October 2021 to date (2023). The ladies in the store are good and willing to help. The problem is the tfg insurance Personnel who's handling my case in the back office. I am not even allowed to speak to that person as they say "you will get a call back. "