Poor customer services

Writing on behalf of my Grand DAD. He is 70+ and he has cancelled his contract that he had a long time ago. now Cellc says that he has to Pay R1038.64 Before he can cancel the account. He ask the agent for the details on when he called and the recording and they say that they can find it. this is real bad customer service. he still has an account and he pays R260 every month why must they rob them. I will raise this to my Lawyer to handle.