Ghosting your Customer

My wife and I bought a outside wooden table and twelve chairs from them in November last year, when they delivered the furnisher they delivered the wrong chairs, we immediately notified them and they asked us to keep the wrong chairs and they would replace them in the next week. Well it’s now the beginning of February and we have sent countless messages cause they only have a WhatsApp line you can communicate on and they either ghost you or make commitments and don’t deliver. As a consumer you make large payments up front in good faith I might add and then they treat their customer like this. My wife has tried to communicate with them on their face book page and they have simply blocked her to avoid any negative posts. They can simply address the matter of replacing the chairs surely but they have zero intention of correcting their mistake.