Lack of customer service or care

I ordered an 18amp battery online and they sent me an 8amp battery instead. Companies make mistakes I do understand, but trying to get any service from them to rectify this has been a nightmare. It took a week of emailing for them to say they were checking with their suppliers, more emailing and Desree said she would refund me on 6 July. I provided my details and since then no response. I received a satisfaction survey in which I indicated the issue wasn't resolved, no response. I've emailed twice no response. I tried calling their line and you can only leave a message, not speak to anyone. Truly ********** service. How does a business like this even operate in South Africa?