Telkom, bad accounting.

I am 75 years old and my husband is 80. We had an internet account with Telkom but they never seemed to get my name right. I was sent an account for Linda Lambert. Very close to my name Laura Lamberti. I went to Telkom because they had cut my internet for not paying her account. Someone at Telkom phoned me and asked if I was S. Smith as my account was overdue. That was the last straw for me. I then chose to go with Fliber. I have used Fliber for the past 18 months. The Telkom accounting service never sent me a bill after I had closed the account as Telkom had cut me off. I now receive a message from Telkom, that they have registered me with the Credit Burea, due to an outstanding account. I need help, please.