booked in twice and still faulty

I booked in my BB 9720 at Moffat on main, Vodashop because my phone was keep on shutting down while on a call or busy with a message ... Then after maybe a. Week my phon gave me trouble again . I called Customer Call and that they said my phone was in need of a software update ... So I went back to the Vodashop and when I got it back after 2 days ... While in the store I waited for phone to come on to see if phone was fixed ... So it happens the phon was still not right ... Now worse than before I booked it in because now I can't even get pass Blackberry I'd ... There technical guy could not help me ... So I went to Vodacom 4U, Walker drive ... They had a look and said my BIS is working but according to them it needs an update !! Now that frustrates me cause that is what the phone was booked in for ... I never have experienced such bad service from a Vodashop before ... And handing back a phone worse than it was booked in for is not acceptable ... I really need someone to step up !! I have 3 contracts with Vodacom , but service like this will make me go to another network as I am already due for a upgrade and next month to .....