Damaged Television

I bought a Television at Lewis store in September 2014 and when I eventually received it, opened it and wanted to try it out, the speakers of the Television did not work. I then reported the matter to the Store Manager and he advised me that they will replace the it with a new one in the week, a month passed and still no delivery of a Television I reported this issue several times and no one got back to me no call to advise me how far thy are with delivering the new Television when I call the manager they always say his busy he does not take my calls and does not answer my messages. Today I called them again and still no help when i called the manager he advised me that his unable to assist me as he is no longer the Store Manager of that branch and the I need to call the new Store manager, I am now really sick and tired of waiting for a new Television, I do not want the Television anymore, because up to date they have not come back to me as they have promised.