HANDED OVER TO DEBT COLLECTORS FOR NON EXISTENT CONTRACT

I was recently contacted by a debt collection company, that informed me that i have an outstanding account with Cell C of around R 26000. To the best of my knowledge i didn't take out any contracts recently with Cell C. I have asked for a copy of accounts but their helpline says the account is closed and that they cant access any info. They have referred me to the Legal dept, who then referred me to the ***** dept, who then referred me to Forensics Dept. I must add its impossible to get through to these Departments, i made numerous calls to them. It was only after speaking to called a gentlemen called Ba***eng via the Cell C helpline that the Legal Dept. called me. The debt collection company wants me to do a affidavit to declare that i did not open these accounts with Cell C , again they are not willing to give me a copy of these contracts i supposedly opened I feel it is unfair to expect me to declare via affidavit a denial without at least seeing these contracts. All i want is a copy of these contracts signed with Cell C so that i can view them , make sure it was not signed by myself and then i can do the Affidavit and put this matter to rest. Cell C is being very unhelpful with this process, their claim of being "the peoples champion" is just a hollow corporate slogan .