Poor ISP / Account management / Customer Relation

i have been shopping online for an internet service provider. When it came to payment screen i cancelled the product because it asked for credit card. I have not processed any payment or product or completed a purchase. Axxess DSL (Pty) Ltd is harassing me with invoices to be paid . i have sent them multiple emails to remove my details from their systems as i am not ready to purchase . i get 4 - 6 messages and emails demanding payment of invoce . If this is the case i will not subscribe to them as an ISP . they refuse to remove . i do not have an internet line or telkom line . I am unemployed . how will i pay for this invoice. I DO NOT HAVE ANY OF THEIR PRODUCTS. yet they want me to pay for it.