E-470 Express Toll Colorado Highway Authority Billed me for for tolls not owed. Aurora, Colorado

This toll company out of Colorado has repeatedly sent me bills for tolls that aren't mine.  They have sent three different bills, with late fees attached, for tolls that I do not owe.  One of the bills was from a collections agency posing as a law office.

The picture of a license plate that was attached to one of the bills was similar to mine, but not mine.  Nor was the vehicle mine. Each time I've contacted them, I was assured by their customer "service" agents that a note would be made to the account not to bill me as the license plate isn't on my vehicle.

I do not live in Colorado, nor have I driven in the Denver area in the last two years, however, they have repeated attempted to collect money from me for tolls on a vehicle that isn't mine. Does this at some point legally amount to extortion?