Ackermans failure to deliver service as promised

I have had a very bad experience with Ackermans. I bought a mobile device in December 2019 and the device just stopped working and it was overheating for no apparent reason. I then took the device in for repairs at Ackermans in festival mall, since it was still within the guarantee/warranty period. This was at the beginning of January 2020. I am now going on my third month and the device is still not back. I find this to be very unfair because I paid for the phone and I am without a phone. Every time I go to get feedback at the store, they tell me I might be getting a new device, but their not telling me when. I am told I should check after 2 weeks. I am starting to think I might not even get my device back in working condition, and might have to escalate the matter to the consumer protection exsperts.