Unauthorized confirmation for electronic directory

I have just received an email from Trudon advising me that I have signed up for electronic advertising at a cost of about R400.00 a month for the next year. As I am a one man show, I know that I certainly haven't agreed to anything of the sort. Having read the above complaints, the only way out seems to be to cancel my debit orders and possibly just ditch my Telkom line altogether. It's a great pity that Telkom are going to lose another customer ,something Telkom can ill afford at this stage.