BE WARE !!!!!!!

I received a form from Telecom 1023 in December 2022 requesting a signature for a Free listing on 1023 and even confirmed by consultant Zenkosi that it is free, however there were some Terms and conditions in very fine print which is highly illegible. The calls continued till January 2023, as was told I need to fill form and send it as soon as possible. In most busiest time of the year, just saw the "Free entry" and signed and send the form back. Now I received an Invoice for R14 400 for a listing that I cannot find anywhere on a website called Telecom 1023. A lady (with an attitude name Jessica) called me asking for payment of the Invoice, i informed her on numerous occasions that i was informed its a free listing as well as on the document it has free. I asked her to send me the agreement, which she did (It was the form that they sent for the supposed "free listing"), this time accompanied by the terms and conditions in HUGE print on a separate page that she attached. I have emailed for cancellation and till this date have had no response. The company numbers go onto voicemail. Now she continues to hound for payment and if no payment is made the company will be blacklisted Is this a legal document and what should I do? Please assist