Defective catalytic converter

Engine noise developed on two year old Chery Tiggo 1.6.Good service record to date.Booked vehicle in for check up,R800 diagnostic later.Informed that the catalytic converter packed up.How is this possible?R17000 holiday fund must now be used for repair.Warranty only covered 1year.Informed by Service centre receptionist, atleast 5 other Tiggo` booked in for same problem.Could this be a manufacturers defect.