NU DEBT MANAGEMENT AND CELLC CONTINUES TO HARRAS ME

I AM SO TIRED OF BEING HARASSED BY NuDebt MANAGEMENT. THESE PEOPLE ARE CALLING ME AND EMAILING ME AS WELL AS MESSAGING ME TO PAY A CELLC ACCOUNT WHICH I HAD NUMEROUSLY ADVISED THEM TO CONTACT CELLC FOR ALL THE RELEVANT INFORMATION. MY CONTRACT WAS DUE FOR AN UPGRADE I CALLED CELLC TO CANCEL THE CONTRACT BECAUSE I DID NOT NEED AN UPGRADE, THE ADVISED I EMAIL THEM A CANCELLATION LETTER WHICH I DID. THEREAFTER THEY CONTINUED TO DEBIT MY ACCOUNT, AFTER CALLING CELLC AGAIN THEY THEN ADVISED THAT I HAD TO DROP OF THE CANCELLATION LETTER TO MY CELLC BRANCH WHICH WAS THE PHOENIX PLAZA, I THEN DROPPED THE CANCELLATION LETTER AND NEVER HEAR OF CELLC AND NOW YEARS LATER THEY HAVE NuDebt MANAGEMENT CALLING, SMSING AND EMAILING ME.......EVERY STATEMENT THAT WAS SENT TO ME ON A MONTHLY BASIS HAD NIL VALUE ON A 30 DAY & 90 DAY ARREARS AND TODAY NuDebt WANTS ME TO PAY FOR SOMETHING THAT I WAS NEVER IN ARREARS WITH. I HAD EVEN SENT Nu DEBT A CREDIT REVIEW SHOWING THAT I WAS NOT IN ARREARS AND THAT THEY NEED TO GET THE FACTS FROM CELLC BUT THESE PEOPLE AT Nu DEBT WONT STOP!