Poor service

I’ve handed my iPhone 6S (IMEI No ********** ********** 2) in at MTN Clearwater Mall for repairs on the 29th July 2018. It just went blank (screen black) after I disconnected it from the charger. (Contract expires Sept 2018 - JHA Nell) After a month (Aug 2018), I’ve contacted MTN Clearwater Mall to find out what the status of my phone was, ONLY then they told me that there is an active app that only I am able to deactivate BEFORE they can even start looking at what went wrong with my iPhone!! I took the phone to iStores in Clearwater Mall to assist me by deactivating the ‘Find my Phone’ app. (And at iStores the technician mentioned that it looks like a hardware problem on my iPhone 6S when I asked.) I took the iPhone back to MTN Clearwater Mall and they send it again to their technicians. I’ve received a SMS notifying me that the repair costs will be R4 470. I declined the quotation on the 4th October. (Job Card No COMCW ********** .) Since the 29th July until today – I’ve phone numerous times and spoke to Christina at MTN Clearwater Mall as well as her supervisor regarding my phone. They both claim to let me know when I can receive my phone back as I said to them I totally disagree with MTN’s technician’s findings. MTN technicians said the problem on the iPhone is because of a human fault, but they are not able to specify clearly what went wrong. I mean, I only try once to switch it on after I take it off the charger!! (I’ve used the on/off button on the side of the iPhone and when it did not respond, I realize there is a problem with my phone!) I suggest to Christina they took the iphone for a quotation to iStores at Clearwater Mall when they received it back as I think the more knowledgeable technicians are at iStores as they are fami**** with Apple and Mac products. I plan to lay a charge of theft at the Police against MTN Clearwater Mall.