Appaling service post online purchase

I purchased two stoves online and only one was delivered (I don't know why), I have been calling, emailing them about the outstanding stove to be delivered and there hasn't been any clear direction. I only got a reference number after sending my complaint. I regret purchasing from Hi-Fi Corporation, it was my first and certainly last purchase from them. Customer service is appalling. The stove is my tenants. How do I explain to them why they don't have a stove in the apartment?