Worst service

I bought a bed at sleep masters in Belville yesterday. I am so disgusted by their service the consultant made an error on the invoice and the wrong bed was delivered instead of double they brought a qeeun size.The consultant which name is Sipho explained to me that they have to sell another bed in order for me to receive the double bed.Thats got nothing to do with me I've purchased my bed cash and now I have to wait . Please if someone can help me .I am a single mom with a back problem and I sleep on a double bunk with my kids I especially bought the bed for myself.