North Texas Tollway Authority NTTA 2 year old bill for tolls with late fees Scam Dallas Texas

Have traveled to Texas from Oklahoma several times a year for many years.  We have to travel down the Turnpike to get to our destination and always paid the tolls in Texas, until they removed the cashiers and pay terminals.  After that there were signs up indicating if you didn't have a toll tag that you would recieve a bill.  Kept thinking I would recieve one but didn't until a few months ago.  The bill was from 3 years prior with a large fee for late payment.  I called the number on the invoice thinking I could explain that this is the first bill recieved that I would be happy to pay the tolls owed, but no late fees. 

The number was only a voicemail saying leave a message and we will call you back which I did.  They did call back about a week later from an unkonwn number, since I didn't know who it was i let it go to voicemail.  It was the NTTA I called them back again but never recieved a second call back.  Then recieved another notice indicating there were additional fees now, but I still could not get through to a person to discuss the charges.  Now about 3 months after the intial bill I have a collector calling indicating I owe nearly $100 dollars for only 2 or 3 actual toll charges.  Very frustrating and clearly some sort of scam to milk more money from out of state people. 

Road you have to travel with tolls + no one to take tolls + signs indicating "no problem we will just bill ya" + bill 3 years later with huge late fees + no person to discuss bill with + authority to have you ticketed or possibly hurt your credit if you don't pay = HUGE SCAM!

Guess I am stuck paying the NTTA mafia or face the consequences.