Refund of Eskom deposit post the sale of our house

Good day, We moved out of our house at the end of September 2021. We were told it would take about 4 - 6 weeks for our refund of our Eskom Deposit (I have the invoice which shows the credit balance), to be reimbursed. After numerous phone calls and emails and a reference to follow up on, we are still unable to contact anyone at Eskom who can assist us, or a response to my query and the reimbur*****t. I'm at a loss of how to proceed to claim this refund.