Mtn technician services

I took out a double- take contract for my husband and I. After 5 months the one phone started giving charging problems. I took it to the MTN store and they said that the phone was still under the 6months warrenty and that was the 5th of January. The phone was booked in by the technicians and after numerous calls to them for feedback on the phone , they gave me the same response Everytime. which was :"sorry due a backlog during the December month we didn't send your phone to the supplier yet". My husband is without a phone for a month now. i'm very unsatisfied with the service of MTN technicians services.