Not able to repair a faulty laptop

I upgraded my data contract with Vodacom in March 2015 and took an HP laptop. Five months after receiving the hp laptop it's screen went black. I took it to the vodacom tygervalley data store in August 2015 and they booked it in for a repair with platinum warranty. 3 weeks later I got it back and was told the battery was replaced. 3 1/2 months later the screen went black again. I contacted platinum warranty and the laptop was collected from my home. It took 3 weeks before I got it back. This time the mother board was replaced. The laptop was suddenly very slow and took up to 10 minutes to start. I contacted platinum warranty again. This time they replaced more components and on the repair report stated that they could not test the device due to it having a password. These same people called me before collecting my laptop but couldn't phone me to ask my password to test the device. This was the third repair on the laptop. And the battery was replaced again. I turned it on after they delivered it to my home today and this time the key board don't work. I took it to vodacom tygervalley data store who sent me to century city repair store and both stores were unable to assist.