Pavilion iStore nightmare!

I can't believe these are the extremes one has to find himself at in order to get hopefully attention from your team. I bought an Apple watch in the iStore at the Pavilion mall in Durban. This was last year in April. The store errorneosuly double charged my account, leading to my account being over the limit by the R4999. I queried this with Standard bank who directed me to iStore. Trisha from the Pavilion store was helpful and promptly responded. She assured me they have sent an instruction to the bank to refund me. It is now January 2020 and I have still not been refunded the due amount to the account. I have sent numerous emails to both Trisha and the Pavilion iStore managers and both seem to be going into a black hole! This is unacceptable. The interest charges on my account and my credit score have been affected by something that is not my fault! I want this account to be fixed asap, and all due interest finance charges to be reversed!