My question involves collection proceedings in the State of: New York

I just got two bills from a collection agency about services provided at a local hospital. The first one totals $235 and the service date was from 7/08-8/08. The next one is for $205 and dated 6/10 and 7/10. I never got a bill for any of these services. I also had health insurance at the time. I am truly baffled why they would all of a sudden claim I owe this money 4 and 6 years later! I am going to call and find out what the deal is with them. It would seem that if I owed the hospital money, they should of attempted to collect sooner!