customer service

I bought a lenovo laptop on the 18th may and used it only 6 times and didn't download or install any software on it but when i tried using it for the seventh time it wouldnt start up as it use to for the first 6 times i then tried restarting it and it was slow and gave me a error saying that i should back up my files coz hard drive if failing i work bad hours so i didnt get the time to take it back untill one day i was off from work then i took it in and reported the fault the lady behind the counter booked it in and said that theyll sms me once its done it took them a week then i got sms to collect. I then collected it and the report said i cosmetic fault then i ask the lady whats the fault she said its software that i installed i then explained to her that i did not install any software then she said to me i must sort out the pc and reload windows so i told her i did not load any software and i bought it like that from them and id like my money back because i dont have time for this i paid so much for this laptop then she said theyll reload windows on there expense and it will take a few days and i am still waiting for them to contact me from the 20th july 2015 and no report yet.