XE500 Tablet

I took a XE500 tablet to Darro for a mainboard replacement, quoted R5000 and replaced it. After receiving the tablet back the sim reader did not work. Took it back to Darro, they said it's the sim reader that's faulty. I took the unit back and ordered a sim reader myself, installed it and guess what? The sim could still not be detected. Took the unit back to Darro, did not want to book unit in because it was tampered with. I phoned in and spoke to Wesley, advised me to speak to Gert who was helpful but explained to me the warranty on the board is expired, it will be over the warranty period of 90 days but he'll have a look. Booked in again and said unfortunately there is nothing they can do. My problem is... they don't want to take responsibility for their stuff up, told me the very first time it's not the board but the reader that's faulty when it was actually the board that's defective. I want a working board or my money back!!!!!