stale burger buns

on Saturday 02/04/16 I had purchased 4 zinger burgers with a large chips and gravy. firstly I was not supp**** with a slip even after requesting one. then when we sat down to have our meal the burgers were falling apart as the bun was so stale. my wife even complained that her burger bun had a smell. the gravy was so weak as well. I then asked to speak to the manager on duty wrt to this shoddy meal. the manageress on duty heard my complaint and could only concede that the buns were from yesterday and I said to her but it is now late Saturday afternoon. where was the fresh buns ? she then stated that she will inform the supplier. what has the supplier got to do with staleness of the buns if the stock is not properly checked. at no point in time was I offered any replacement on my meals. the only thing that was replaced was the gravy. come kfc don't pass on stale food to your customers please. we pay for our food and I expect quality in return.