Absolutely no service

I had problems with my device, iphone does not switch on (only show's an apple). So i booked the phone in, all good and well, got a msg about a week later, phone is ready for collection at festival mall branch. I phoned festival mall branch, mam please dont phone us, we will phone you when the phone is here. Off course i do not get a call and has to phone them after 3 days.

Go in to the store, get the rudest service ever!! "Please take your phone mam and put the icloud off" I say I cant cause the phone does not switch on. Serisouly Cell C, how should I switch the icloud off, the phone is brocken and doesnt switch on. So the lady very rudely said to go plug it into your pc and do it like that. Still doesnt work as the phone doesnt switch on so the pc can read it.

Soooooooo fed up with bad service from cell c!! Have my phone now, still brocken, still not switching on-cant go back to the store cause they dont understand THE PHONE DOESNT SWITCH ON AND IS BROCEKN, HAS TO GO FOR MOTHERBORD TESTING!!!