I just want my refund after faulty product, it has been more than 3 months!!!!!!

I have had a very bad experience with Makro the past 6 months. I bought a Meccer inverter from their online store for R3 200. After it broke 3 months later, it took about 2 months for them to fetch the inverter, as it could not be returned to the store as I bought it online. The inverter was collected in February and I sent follow up emails every week requesting on the progress and when I'll receive the inverter back, as I work from home and need it to work with all this Loadshedding in SA. For the 1st week I got a response indicating that it is at the supplier and they are working on it, but after than, no response what so ever. I continued to email them once a week to follow up on the matter with no response from any one. Finally beginning of May they sent an email after I followed up again, indicating that they cannot fix the unit and will refund me. I immediately responded that they should refund into my bank account as I no longer have a Makro account. I provided the details of my bank account and even attached a Proof of Bank account letter, once again with no response. I phoned the call centre early last week to follow up on the refund, after the call got dropped a couple of times as they tried to follow up with the finance department, I kept on phoning for an answer. Finally I was told that they tried to refund to my account which failed. I explained again that I told them not to refund into my account and provided banking details. I was assured that the process would take 24-72 hours and that I would have the monies in my bank account by Saturday 13 May. I phoned again this morning, each time the call got dropped when they put me on hold, each phone call lasting between 7-15minutes and I have to pay the costs. This is pathetic service, I can't even buy the exact same inverter with the monies they will one day refund me, as it is now a R1 000 more. I just want a date for the refund to be paid in my bank account and no one can seem to give me an answer, and if you go into the Makro shop to speak with a person they just tell you, sorry, we can't assist as you bought it online. My next step is to take it to social media and reach out to people in Management on public spaces, so people can see what bad customer service Makro is giving people....my monies wasn't broken and now I need to spend extra cost to find somewhere else to work, while Makro takes their time to refund me!