Worst after sales i have ever came across

I booked my phone(lumia 950) in with MTN insurance for a broken screen and software issues phone returned with a fixed screen and new rear cover software issues stilll existed. I re-booked my phone with MTN in Cavendish sqaure for repairs on the software issues phone returned 10 days later with the same issues. Re-booked phone again returned with the same issue still has not been sorted out. Re-booked phone for the 4th time my now hasnt been returned five weeks later each week i have been told by the store aswell as the repair centre that my phone will be returned the next week i still dnt have my phone. i Pay R639pm for my phone including insurance aswell as every single time i inquire about it i am sent to different people and each person canniot give me a proper answer or take responisbilty for this huge delay the last i heard they were blaming the courier company DSV for delaying the delivery. I want my phine contract cancelled with MTN and i want my phone or a new phone returned to me without paying a retention fee in total i have been without a phone for 4 months and counting. MTN has the worst after sales service i have ever came across aswell as the MTN store in cavendish completely unproffessional the manager himself couldnt give me proper information nor did h follow up with me till today i have heard nothing i will nerver renew a contract with MTN again i want my contract cancelled immediately aswell as my phone cause i am taking this situation to the Ombudsman. E-mail ********** tel: ********** 434