Absa - service for premium banking customers not acceptable!!

On 19/06/2018 I followed up per email with the disputes department about a dispute that have already being lodged on 27/04/2018. Until today I have not received any telephone calls or any communication regarding my follow up email on the dispute which was send on 19/06/2018. This dispute involved an agreement that was cancelled with an supplier on 28/02/2018, and the supplier is still refusing to refund the deposit of an considerable amount of money. A chargeback needs to be done as the supplier insists on a letter from the bank that the chargeback will not be processed before doing the refund, but this company cannot be trusted. I therefore request that the chargeback is finalized by Absa as a matter of urgency as it has already being delayed for a too long period. It was expected that as a premium banking client that the service would be of a higher standard as to what I have received this far.