Ruining my credit reputation and wasting my time

<p>So, a couple of years ago there was a ********** Cell C contract opened using my details.</p> <p>After months of back and forth, the case was finally resolved and a letter of confirmation was sent so I can send to anyone checking my record explaining that it was ********** and I don't have a contract with Cell C.</p> <p>Fine and well, however, Cell C sent my details to the NDS and 2017 they still contact me telling me I have to settle my Cell C account. I have repeatedly sent them the letter I received from Cell C but they still keep calling me years later.</p> <p> </p> <p>Now Cell C - tell me what I must do with these rude as hell people telling I need to pay you your money??????</p>