Defy lack of after sales service

I bought a new 5burner / elec oven defy stove from Makro. My qualified electrician husband installed the electric cable. When we switch on the oven it warmed up but the fan was hitting against the body of the stove. Clearly during the manufacturing the fan was not properly fitted. Now they don't want to assist us because my husband according to them are not qualified to install an electric cable. His qualifications has nothing to do with their manufacturing mistake.