damaged my phone instead of repairing

On the 6th-01-2015 I handed in my phone for repairs in mall of the north branch because it was switching on and off on its own. On the 21 of the same month I received it back, but now the problem was evertime I make/receive calls the other person can't hear me due to damaged micro phone I guess. I went back to the store to try and sort out the problem however I was told to hand in the phone again and wait another 3weeks of which I thaught its pathetic. Luckily my contract with them will expire soon and I will just cancell it and take my business somewher else where they will treat me well. My repair ref number was: PRE 584988.