Dishonesty

I bought my son a boot worth R420 at three rivers on the 15/05/2018, the zip broke so I went to the store yesterday on the 27 of November to ask if is possible for them to change it. Was just trying my luck but according to my knowledge and understanding factory fault is 6 months so the store manager told me is 3 months i felt offended because I know is 6 MONTHS. I called their head office and ask, the lady who was helping told me that she can't change what the manager told me but she can help me with lodging the complain and the complain department will call me within 24 hours and I'm still waiting for them to call.