Bad customer service from a senior

So on the 17th of Jan went to eyethu mall pep home to pay for my decoder went in straight to the queue where I was visible to security and cashiers, with me I had a small shopping bag wich had my purse bby bottle and a nappy, one of the staff asked me to go put my bag at the counter and I told her I cdnt since I only had the above mentioned items, which resulted in her being rude towards me and ordering the staff not to help me, she even called customer whom I spoke to and explained wat was going on, to my surprise the lady I was talking to was surprised I then told the consultant that I was going to escalate the she said I should and include my contact details. My question is why was I treated like a ********, shouted at by someone who's a senior in front of her staff and other customers. I then asked for her name she said I should look at it myself since she was wearing a name teck. Her name is Helen at eyethu mall pep home in Stretford orange farm My contact number is ***