Minors cannot cancel TV Licence!

We took out a TV Licence 4 years ago when my son was 16 years old, we could not buy a TV then because they said he cannot have a TV License he is under age. So I phoned SABC and they send me a letter to take to the police station for an Avidafit, I then email it back to them. I phoned them after I send the mail and they told me that Shop where we bought the TV should be closed becuase how can a minor have a TV Licence. I told them we never bought the TV , I had to take out a TV Licence of my own to be able to buy the TV, thats why I need to cancel that one of my son. She did something on her side and last week I received an sms, saying : Jj Koch, we are proceeding on your TV Lic acc ********** 52, Make an immedeiate payment to stop the process. I went online on his number and I couldn't believe it the account is on R1855 now.