Clearance Warehouse cousing old age parents hypertension due to incompetency

My parents bought couches cash at Clearance Warehouse and we collected them on the 5th Feb 2021 and we had to transport them to Winburg in the Free State on the 6th Feb. Upon our arrival when we assembled the couches as they were in boxes only to find the L-shape couch is incomplete the other side is missing or incorrect to form the L-Shape, we immediately contacted Clearance Warehouse and sent them pictures, they thereafter agreed to exchange and replace the couch, to date they sending us around and even after they promised to refund. On the 20th Feb they told us that they can only exchange the couch end of April and that is after they failed to honour the agreement to exchange the couch on the 21st Feb. We have been dealing with the store manager by the name of Lowie and Ellen, after sending them the banking details to refund they now ignoring our calls. My parents are frustrated and they are pensioners to think that they used their pension money to buy the couches and now this, they even scared to seat on those couches trying to avoid damages.