Car back window

The back window of my car was smashed (following an attempted *******) and replaced on 22 October 2015, at Cape Town Auto Glass, Elsies River with the cost of R 840.00. <br> Less than 24 hours later (23 October 2015) the same, newly replaced window was broken again. This was not due to an accident or attempted theft . It appears that the window was not fitted or sealed properly when it was installed.<br> I immediately called them and following their request, took the car back to them. At this point they advised me that they can not do anything because there was no guarantee on the placement or service provided! I really think this is pathetic!<br> 1) If this was the case, why did they not simply confirm that there was no guarantee when I spoke to them telephonically? 2) How is it that in less than 24 hours the windscreen shattered again without any impact? 3) My consumer rights, I feel have been infrin