Samsung Broken My S7

<p>I took my cellphone in for ADH and it was working up until I handed the phone in . I heard nothing for 2 weeks until I called them to find out and then I was told my phone's mainboard was broken which would cost R4500 to repair the device . I do not understand how it is possible to hand in a working device to have it been working by Unitronics . Tatum Walker is the lady I spoke with and she has no regard for consumer service and everytime I have to call her back about my cellphone .</p> <p> </p> <p>I am honestly angry I don't know what to do and I would like Samsung to handle this matter because I handed my device in by there store. Its 2 months now and I am still without a phone</p> <p> </p>