Refusal to disclose info. Threats re payment

The said supplier called to sell their service. I requested that they send the info so that it can be viewed before decision is made. Thereafter they constantly called for payment. Speaking to a lot of people daily, I confirmed payment on the 15th as I pay all suppliers on the said date, not realizing I spoke to them. Next moment I am being threatened and forced to pay. They utterly refuse to disclose the voice recording they claimed were taken with the initial call, yet they will refer back to what was said on the recording. They are threatening to do damage to the name of my company on social media and to list it on ITC. The manner in which they communicate via email is utterly disgraceful and I cannot believe that they are so unprofessional! They disclose no contact info or address on their website [URL Removed]