********** account closed at cell c but I’m still getting calls and SMS’s

In Dec 17 I had someone opening 4 cell c accounts **********ly using my details, I since then been to cell c store to report the matter gave them an affidavit, ID copy and 5 signatures, the accounts where closed but I’m still getting calls and sms and the account is still showing on my credit record, I have been to cell c store numerous times to ask for assistance but with no help. Please can I get some assistance with this problem.