Failure to repair and provide excellent services

I bought a cellphone at Daveyton Mall Ackermans on the 04 March 2017 name of the phone is Mint Fox which costed R399. The phone took only five months working properly until it didn't turn on when i switch it on,had battery problems, screen problems and overheating. Since the phone had problems i had to send it back to purchased store Ackermans on the 28 August 2017 only to give me 21 days of repairing the phone i went back after 21 days on the 27 September 2017 to check on the phone the receiving lady said i shouldn't come there if she hasn't called me to come fetch the phone with attitude. I went there the next day and she said the phone couldn't be repaired at the centre so they will give me a new phone but i should give her only a week to get the new phone to replace my phone, as agreed i went back there after a week to fetch the phone she told me that the repair centre hasn't sent any phone to the store i should wait she will call me back as soon as possible she receives the phone. As spoke to the manager of the store i went there again to check the phone she tells me that the repair centre has courier the phone to a wrong address which is Cape Town she try and talk to the MTN Repair Centre in Midrand again to follow up on the matter. On 14 October 2017 i went to the store again the manager said to me the phone has been sent back via an overnight express from Cape Town she is still waiting for the phone but she will follow up on the matter as promised she will call me on Monday at 10:00 am to inform about the matter. She called on 16 October 2017 saying that she called the MTN Repair Center in Midrand again to find out about the whereabouts of the phone she was told by MTN Repair Center that an email has been sent to Cape Town store to send the phone back to Gauteng but still there is no positive input on the store replacing my phone i need assistance in this matter.