Studio88 refuses to return my purchase with everything attached

I bought a sneaker at Studio 88Nonqubela centre site b in khayelitsha and according to what i was told and what is on the slip it clearly state that i can return my purchase along with the slip and the item needs to be in its original condition within 30days of purchase. Regardless of all that I’m now being told I can not return a sale item and i ask for a manager he/she is never around the lady who helped m says she cannot help with head office number as she does not know it. I do not understand how I cannot return my purchase whereas I was never told about your policy on sale item upon purchase. Stop selling us things on false pretence