Game stores keywest is pathetic and selling customers broken machinery.

Bought a sewing machine for my mum from game stores in keywest, JHB. The machine was delivered broken and faulty. She took it back to game stores in Keywest and instead of replacing the unit, which was brand, new, Game sent it in for repairs. When she fetched it, they gave it to her without a foot for the sewing machine. Moira at game keywest, is not helpful at all. Why is this unit not replaced as it is brand new????? Why is it being fixed and why must i pay for a unit which was broken, Game stores is truly pathetic and i want a refund which they refuse to give.