Demanding money not due

Hi,

In 2016 I paid my TV licence but kept on receiving demands from SABC to settle the account. I sent several emails providing the proof of payment. In 2017 I did not want to pay for the year since they were not acknowledging my payment for the previous year. So my husband purchased a license on his name and I sent through the payment to SABC and requested that the license on my name be cancelled as we had valid license for our household for that year. Later I received emails from Nudebt stating that I had not paid for two years. I sent through all my communication and they were satisfied with what I had sent to them. They said they would escalate to SABC. I have since started receiving mails and sms demanding R697.00. I do not like to be in debt and do not want to be listed for something that I have paid. Please advise what do I do.

TIA