Refusing to refund an item that is not able to be used for purchased intention - Consumer Complaint for MAKRO - Head Office

I bought a cellphone cash from Makro in Woodmead and they refuse to refund me as the phone has no signal on any network so I am unable to use it for its intentioned purchase,the took more than an hour to collect the phone for me at the store and refused to test it when I purchased it,we agreed when I phoned customer service to refund it due to all the holidays before 10 Jan from 23 Dec purchase date and when I drove back from Rustenburg to Woodmead on 9 Jan they refused to refund me,they told me to leave the phone there which is completely useless as it is not a defective issue and doesn't resolve my issue. Please help me resolve this.