Refund on layby

I made a layby at Sterns Waterfall mall Rustenburg, my layby expired and Sterns sent me a message to go collect my money at the branch. When I got to the branch they did not have cash. Instead they requested my banking details and promised to pay me within 7 working days. After 7 working day no payment was done. I went back to the store found different people they told me the payment would actually take 21 working days. I waited 21 days has past no payment is made. Sterns is refusing to refund my R10 000.00