How many times must one respond to SABC regarding TV Licences

SABC keeps sending me requests to pay my TV licence as well as their debt collectors. I have responded to their requests to let them know that I sold my house and all belongings last year and that I have been in Sweden and will be relocating to there and will no longer require this licence, however, they continue to send me requests and warnings and have now started contacting my son in this regard. How many times do you need to be provided with this information. I have also offered to provide them with copies of my passport to show them that I have been out of the country and although I have now returned for a brief visit, I will be returning to Sweden as soon as my paperwork has been completed. I had this same problem with my parents licence some years ago and it took me almost 3 years to sort it out. I will not do the same this time for my licence. I have sent numerous emails to which they have not responded. Catch a wake up, SABC ... I will not be renewing this licence.