BAD SERVICE - PCC CELL REPAIR CENTRE

I paid R1500.00 to repair the screen for my phone. 4 months down the line the screen just went blank. It was clear that the Technician Bilal did not do the right job. I went back to the store to report the problem. I gave the phone to Bilal who told me it's a minor thing and can be fixed. He later told me that I should pay R950.00. I do not understand why I should pay an additional R950.00 for the screen that has not chipped or damaged. The screen was not even properly fitted. I tried to tell him that and he said if I don't pay then he can't help me. How can I pay R2450.00 in a space of 4 months for someone else's negligence? On the other hand, the owner of the shop after hearing the whole story he told me the screen does not have a warranty and I must just leave because they can't help me if I don't pay additional R950.00. I was not even told that should the screen go blank after a day there is no warranty. It is not even written on their receipt/invoice. This is a total ******* and a ***** way of making money.