Delayed by Cell C

I got a call from a ***** department telling me thatan account has been opened using my lost ID. I went to Cell C and thy scaned my affidavit and told me they investigating. I have been calling Cell C since last year October to find out if I can get a letter that states my problem and they keep asking me the same things and they always tell me they will get back to me within 48 hours of which they never do. I need a letter from Cell C that shows I am not the person who opened the account because I need to apply for ***** protection<br>