Cancelled Contract whithin 4 days, but blacklisted

I cancelled my cell phone contract that did not work, within 4 days after receiving it ,on Telkom's advice. Telkom made me drove 350km to return the phone. After cancellation, I still received bills. I spoke, on my cost, to numerous supervisors at Telkom. They locked complaints and promised to phone back with a resolution. No one has ever phoned back. My bill is still rising and they can't seem to tell me for what. They have blacklisted me and I cannot get any loans at the bank for my Business. My lawyer has locked a formal complaint with the consumer law, but I can't seem to get this sorted yet. Can you please help me?