Customer Service

We received a Telkom wireless phone, and for some reason we cannot receive incoming calls from mobile phones and some landlines, the only calls we can receive is from others using the same Telkom Wireless phone. I have visited one of the Telkom stores twice now and logged 4 faults and 3 of the faults were closed without resolution - surely this amounts to dishonesty. I sent an email yesterday and was advised to call again - I just need Telkom to make me understand what is the point of calling again to log another fault and go through this vicious cycle once again. Is there anyone at Telkom that is going to take ownership and help resolve this problem or do I have to cancel my service with Telkom. I don't think I have ever experienced such bad service from any service provider before.