Blatant theft

Blatant Theft. My daughter in law bought me a shirt for Christmas. She never retained the slip or gave me the slip as the price was not disclosed. The shirt was far too small for me and I took it to Truworths, Somerset West to swop for a larger shirt or buy a different shirt if there was no stock. I must make mention that the tags were still on the shirt when I attempted to swop out. I was abruptly told that by the manager that Truworths would not swop the shirt out as I was not in possession of the slip. I said that the shirt was given to me as a gift and I do not have the slip, but to no avail. I left the brand new shirt with the manager as the shirt was of no use to me. Please people, beware of this happening to you. I have never experienced this ever before.