Environmental Safety Intl PO Box 397 Fairview, NJ 07022-0397 Keep demanding payment for product that has been returned. Unopened. Fairview New Jersey

October 10, 2017 I get a phone call out of the blue and a company representative explains the product.  Says I can try it for free up to 30 days.  It is a powdered enzyme you can flush down the toilet and supposedly it eliminates the need for pump outs and reduces sludge and odors.  I received the product but about five days later returned it by UPS ---UNOPENED.  Three days later a company representative calls me asking how I would like to pay for the product, but I said it was returned.  Unopened and by UPS.  Today--11/30/2017 I get an invoice in the mail requesting payment of $159.00...I wrote on the invoice that the product was returned and you were informed over the phone as well.   No payment is due.