Bad service

Bought a skirt from Mr Price in Greenstone today unfortunately when I got home the skirt was small. Decided to go get and exchange at the Mr Price at Norkem Mall. To my surprise I couldn't make the exchange cause the item was not appearing on their side and for that to happen it takes 24hours . With the rude cashier with no name tag helping me, she just told me to go back to Greenstone. No where on the slip does it state that to make an exchange at a different store one needs to wait 24h.