CANCELLED CONTRACT A YEAR AGO... NOW HANDED OVER... for what?

Worst place to deal with as you get no response. *** does not get back to me!!!! 6 April 2022 I cancelled a data contract with Cell C. After a long struggle it was cancelled telephonically on land line *** (wich is no longer operational, as that was also cancelled). They deducted money the end of April, as my cancelation was considered late, which was fine, as that would be the last. Now MORE THAN A YEAR LATER I have been handed over to NDS !!! What for???? I had a data contract with no devices or phone, just a sim card!!! So *** sends me Cell C Customer Service Case Number, but no one ever responds to my mails. I have even started complaining on social media about their lack of service. ***. I understand it is not their department or job to sort out account, but where else do you go when you can't find any contact information or response. ABSOLUTE WORST PLACE TO DEAL WITH!!! WOULD NOT RECOMEND THEM TO ANYONE!!!