Unacceptable service

I left my son’s phone on 1 April because it’s not working. To date I have no movement no feedback whatsoever. I called earlier today and left my number because the technician is on lunch and was to return my call. He didn’t. I called now and the technician has left. I asked to speak to the manager and as usual the the manager ‘ extension just rings until I cut it. I called a few minutes later and they didn’t even pick up my calls… when I left the phone they said 14 days but they will send my a job card.. it’s 14 days later, no job card, no response, nothing.