Telkom Nightmare Service

We were advised that our copper telephone line was to be cut off and that Telkom would supply us with a free phone which they would send via courier. This was duly done and this phone worked for a week. As the phone worked we threw out the box and delivery note. This phone stopped working just before Christmas and after visiting the Telkom shop in the Galleria KZN, we were advised that the phone instrument did not work. We asked for a replacement but as we were unable to produce the delivery note they could not help us. Since then we have tried numerous no's to ask who can give us a phone that works and we are being pushed from pillar to post. We have a fibre line that works but a phone that Telkom supp**** that does not. How can I get a replacement???