Tablet booked for repairs at Cell C for more than 3 months

I booked my nephew's tablet for repairs on 02/01/18 after the back side of the device exploded, device was collect at my house on the 11/01/18 by the courier company, today is the 21/03/18, I have not received the tablet from repairs department, no feedback from Cell C, after numerous times of calling the department and not spending less than 20 minutes on the call with them, with no solid feedback.

I was told that when the decoder was received by Cell C, the receiving department did not capture my device details and they are unable to trace it, they promised to call with feedback more than 3 times. No device & no feedback till date.

The sad truth is that my nephew is has not tablet and I bought those 4 tablets, for education reasons, none of the 4 tablets are working, booked 2 for repairs and was told to pay R1600 to repair each tablet. And I am still paying for the 4 tablets till date.