Terrible service from Decofurn

I had purchased a few things from Decofurn on the 24th of November 2017 (3 weeks ago) including a cupboard. However once I had started setting it up, I realized there was a missing piece. I immediately contacted the store and was told they'd deliver it the Sunday. The Sunday they contacted me saying they're out of stock and would deliver the missing piece by the Wednesday. By the Thursday I still hadn't received it, then contacted them and spoke to the dispatch manager and explained to him that I'm still waiting for the missing piece and who'd then be responsible for assembling the cupboard as I've already paid someone twice under the assumption the pieces would be here (as promised). He said his expecting cupboards to be in by the Friday and he'd send one of his guy to come and assemble it then. The Friday just before 18:00h one of the employees had dropped off the missing part at my house and was told his only to drop it but he can assemble it at a rate of R200.00 and I refused to pay as that was not the agreement I had made with the manager. Then the following week I had contacted the store thrice on the last occasion the guy had said its not his duty to assemble but he'll come and do us a 'favour' that afternoon and his YET to pitch. This morning we then went into the store to speak to the store manager- who said he has 'TOO many things to see to' therefore since hasn't returned ANY of our calls. He said he'd send someone today still and I'm still waiting. I've had a BAD experience with Decofurn, 3 weeks after purchasing the product after constant contact with the store and dealing managers who are 'too busy' to ensure customer satisfaction.