******* charges on a faulty but new Cellphone

I purchased a cellphone from Foschini in December 2017. The phone just out of the blue went dead in the beginning of March. I immediately took the phone back with the box and papers. The phone was then sent to Mobicel to see what is wrong. I was in the interim told I will get an sms from Mobicel as proof that they received my phone and to date this has not happened. I went to the store on Sunday past and to my amazement I was then told that I must pay an amount of R867.00 to have the phone fixed. The manager of the store was also baffled as the condition of the phone was immaculate. No marks, no scratches nothing. The phone not once fell either. I bought a glass screen protector that is also still in tact and it has a cover. According to the technician the phone is damaged. The manager of the store says they have been asking for the report for the past week and to date nothing and even I tried to call them and no one answers at all. I am utterly disguisted that this is the way they are treating there clients and to top it all they want me to pay R867.00 for a phone which cost me R1000.00. I am still well in the year guarantee period and to top it all the credit ACT states that they must either repair the phone or replace. I am not going to leave it like this. I want the phone either fixed, refunded or a new cellphone and they must not even try and want to charge me.