Fault on upgrade contract

On the 31 of August 2015 I went to 4u in the paarl to upgrade my phone.The guy that helped me looked half a sleep. I asked the sales consultant at reception if the have the sony z series. he rep**** and said no they don't make it anymore. (a day after that some of my friends showed me their new phone and it was the z series.) Then I thought there's no z series so I told him its fine ill take the xperia. on that Friday the 4th of Sept I went back and said there's something wrong with my phone and that my friends got the z series and asked why did they told me the don't make it anymore. The did not help me with my phone that day, and I also told them I work from 7:00 to 19:00 every they. They also did not tell me that if there is a problem with your phone to bring it back under 7 days. I was 7times at 4u in paarl at different dates if it was not more. every time I went I complaint about my phone that wont download app etc, then my phone made lines on its screen. they send me to a different town, they told me its my lcd, so I went back to 4u a different day and now the accusing me of that I must have dropped my phone and I did not dropped my phone or bumped it. it has a cover on.