Bad Service

I bought clothes for more than 3500 cash at Truworths one of the skirts I purchased for R650 doesn't fit me. Went to Truworths Sandton City the Manager refused to exchange the skirt to a bigger stating that if I don't have a receipt they will not exchange for me I told her I don't want a refund I WANT TO EXCHANGE YOU KNOW SHE JUST LOOKED AT ME. I want to know is this how you treat your loyal customers.