Extremely Disappointed!!!!!!!

I bought an Itel cellphone at Mr. Price Tablle Bay Mall, They gave me a ten-day guarantee if anything happens to the phone in that period they were going to replace it, and after that, it will be on a warrant for a year. I used the phone for 12 days and the screen just went blank, I took it to the store and they said they will send it to their technicians and it will take up to twenty-one days to fix the device. After twenty-one days I did not receive a call from them to update me if the device was ready or not. I went to the store and I was told that they do not know anything about the progress on the device and I must come back after a week to check. I went to the store again after a week and I was told the same thing again by the manager he promised me that he is going to follow up with the technicians and give me a call that afternoon to update me. It has been another week now I still have not heard anything from them. It's been eight weeks now and I have been going through life without a phone. Asking colleagues to use their phones so I can call my kids' creche. I do not have money to purchase another device or an extra phone to use at home. This has inconvenienced me and it is so frustrating that a huge business with a reputation can have such bad service. I am extremely disappointed.