Getting less than what you are paying for

Getting way less than you are paying for. I bought the pulled beef pie from Woolworths, claiming to be 1Kg. When I opened the box, I was shocked with how little was in there so weighed it. With the packaging, it came to 834 grams instead of the 1kg promised. After cooking it, it went down even further. Don't charge me for 1kg if you are not giving this to me.