NO SERVICE

I took out two laptop contracts with MTN at parktown about a year ago, HP laptops. These laptops are very problematic they are very slow. One of them has shutdown it won't switch on. Since I took out the contract I seem to have misplaced the copy of contacts I was given for these laptops. Now... I need to book these laptops for repairs, the store that I had taken these contracts has since closed. For the past two weeks I have been requesting a copy of my contracts and i'm being told different stories every time I call the call centre. Can somebody assist, I need to have my laptops fixed.