How do I return a product

Bad service. I buy 2 chairs from the Montana store and got them delivered but..... Spoke to a sales consultant and they told me to take it back to the shop. The chairs where to small so I toke them back to buy something els. They could not assist me in the shop. They have to come and collect them at the place the where delivered to. Now tell me how does that work? Someone needs to get the story right. I from 40km to this Mr price shop.