Refused refund

I bought a phone at Ackerman's in Jabulani mall Soweto on the 5th of May the battery was too hot had to return it back on Saturday the 11th with everything proof of payment, box, headsets, and charger. The salesman said it non refundable they can only send it for repairs it will take a month for to get it. They do not call me to inform me what's going on with my phone I'm surprised when he said it non refundable because on the till slip it says I should get a refund within 30 days. The severoce is poor. I went back last weekend another sales person is telling adiffernt story. Please help i need my money back or they should give me a new phone.