CELLPHONE WENT MIC @ FOSCHINI LAKESIDE

I took my cellphone in for repairs at Foschini in Lakeside on the 13 Of March 2018. To this day I have no tangible feedback. After three months of no communication from Foschini, I contacted them to inquire about the progress. At first the lady at the cellphone counter( Lindiwe)told me she can't find my documents in her file, she will wait/contact the person who was accepting my phone to find out where did she file the papers. I then called her the following day, still I received no concrete answer. A week later I call her again, she then asked me for account number and asked I describe what was wrong with the phone, and also asked me to confirm if I left the phone at Foschini. This clearly means Foschini has no idea where my phone is, and there is no paperwork to prove that I handed in the phone. Luckily for me, I insisted for copy before leaving the shop when I was handing in the phone. I need managerial intervention at this stage. The phone was still under warranty and it was insured via Foschini. This is the lowest form of customer service I have ever experienced . Today I called Foschini Lakeside for the umpteenth time, and I was advised that they are not sure when will I receive my phone back. Is it unreasonable to get upset ,three months after handing in your phone, and I still have no satisfactory update? There is a reason why I bought a cellphone, I would like to utilize the phone please, sometime this month would be good . Three months is more than sufficient time to repair a phone, can somebody please do something and get my phone back to me