Pathetic service

I purchased via online in August. The incorrect product was delivered. I queried this with the Witbank store as it was delivered from this store and was told that nothing can be done from their side and I must take it up via national customer service centre. I have loaded a request and been struggling since then to get product exchanged or a refund issued. This has been escalated several times with no response. I am always promised a response within 24 hours but this does not happen and I have to keep on calling to follow up.