Mr Price
Paid for an item that I didn't receive

I did an online order, I received my order today and to my surprise one item wasn't included. I paid for the item, but when I called the customer service helpline the lady told me that I would have to send them a bank statement. This is a waste of my time and money. She says the item is out of stock, so it is their responsibility to remove it from the website or notify you before you purchase it. They are able to see what I paid, but I must still give a bank statement? This is very unprofessional