Billing never ends

For five months now I've been receiving billing notices for a blood test performed in October 2006. How many years from now will I be receiving bills? It would probably only take a few phone calls to resolve with the insurance company, but I put it off month after month.

In a new twist, today I received a refund from the company who supplied home care supplies in January 2007. In reviewing their accounts they realize they overcharged $45. They've sent a check made out to Robin. It's a good thing her name is still on the checking account...