Trudon and Telkom - A contract that does not exist!

We were called to renew our entry in the White and Yellow pages, but declined. However, we have been billed and now have a monthly contract amount added to our Telkom bill. We have contacted Trudon who cannot assist as they are working from home, Telkom cannot assist as the contract exists between us and Trudon - how do we stop this? We do not have a contract, and if I do not pay my Telkom bill my lines will be cut, and we are a business... Phone Telkom every month to escalate the dispute, but 4 months later absolutely no joy...