Rude customer care agent

I placed an order on the 06th October for appliance, out of all the items I only received 4 of them after doing follow-ups myself. My order was allocated to Rene who happens to be very rude, every time I call to follow up on my order she shouts and just becomes rude and today she dropped a call on my ear when I enquired about order, she first shouted at me telling me that there's no stock and I know that coz she told me last time, I have never been so humiliated in my life. I don't know why she works at customer care if she has to be this rude. I demand an apology and I want my order sent to me ASAP.