Ignoring problem

I been trying to get some feedback for more than 4 months with regards a faulty waterproof Sony z3 after taking it back 3 times they just say they will respond shortly then they sent their own courier to collect the phone i have thr picking slip still to prove it but they say they did not recieve it. Then they phone me whilst im in lectures and cant talk they left messages they will respond but still they just passing the buck im absolutely shocked at the service they seem unorganised and clueless. What they getting paid for can i also get a job at vodacom please i can also treat customers like ******s