Dont answer phones ir privide feedback

I have been complaining about them nit answering their phones. Got feedback that this will be reported to the regional manager. Still no difference. Called about 20 times in 2 days. No answer. I also handed in my phone. They gave me the nr of the high value repair centre. I had to follow up and found out they only recieved the phone a week later. Last Thursday the repair entre said they sent me a new phone. The one I got hold of the shop this week they told me they are using a new courier. The repair centre and shop is in Cape Town. It's been a week and the phone haven't arrived at the shop? This is week 5 after sendi g in a brand new phone.