Unacceptable Service

My iPhone 6 freezes and always shows the apple sign until battery goes flat.I took my phone to an Apple store in Nelspruit where they tried to find out what the problem was, but could not determine the problem.They advised me to take my phone back to the store where I purchased the phone as it was still under warranty.I then took my phone to Vodacom Piet Retief to send away for repairs.They send it in and after a week they phoned me to tell me my phone was fixed.When I came home and inserted my sim, the problem was still not fixed. I took it back again and they told me they going to send it away again. A week later, I received another call from the branch informing me to fetch my phone. When I got there, Natalie told me they could not work on my phone as the 'find my iphone' was active. She then said she would take the 'find my iphone' off from my phone via icloud - I should just give her my login details. This I have done. When I came home, I received an email saying my iPad had been erased.I phoned again today for progress and was only informed to phone the repair centre myself. When you phone the number they gave me, it only goes to voicemail. I have had enough!