C B D Toner Recharge

I cancelled my Internet service in 2011 or 2012. At the time of cancellation I was not told of any money owed. I never received a bill. I never received any communication from them stating I owed them money. Today I received a collection notice in the mail. I called them and they told me they sent a bill in December 2012. I never received the bill or I would have paid it. I never received anything from them stating I owe, or that they were sending it to collection. How am I supposed to know I owe them if I do not get anything saying I owe them. I was a customer for over 10 years. I never had a late payment fee or missed a payment. To get a notice of collection is very upsetting. I don't want this to happen to anyone else. I want others to know what they did to me so it won't happen to them.