collect pros Payments made easy i got a letter saying I owed 79.95 Carson City Nevada

I have received a letter from Collect Pros saying it's an attempt to close my account. supposedly I owe $79. 95 dollars . And if  don't pay that by May 03, 2015 I'm going to have to pay $99.95. Because there is $20.00 dollars collection fee. 

Of course I'm disputing this. How do I owed $79.95 for some free trial I didn't even get. and have no recollection getting anything. And when you call to see what this letter is about, the only thing you get is a machine you can even talk to nobody. Last but not least all the machine wants is for you to make a payment.