DEFY - A COMPANY OF GHOSTS

We have been trying to get Defy to repair an oven for 6 weeks. Baking is only source of income - so for 6 weeks no income as explained to customer care. We have phoned customer care, we have emailed, we have phoned different branches all in the hope of getting some sort of reply. We have given job card numbers, proof of purchase, repeated the same conversation over and over - still not a single word or telephone call about this problem. WHERE DO WE GO NOW????????