what if my lender after 2 years has found out that their original map interpretation was wrong and we now need flood insurance?

Then you may need to look into getting flood insurance. there are times that the flood zoning is adjusted.

It may not be the lender looked at the map wrong but that they adjusted the flood zones. You will need to address it with the lender but you are likely going to go ahead and find some flood insurance

It doesn't matter if the map was wrong, or the flood plain changed to where you property at one time was not in a flood zone now is, then under the security agreement you signed when you purchased your home, you have to have flood insurance. If you don't buy it, then the lender will add "Forced Placed" insurance, (VERY expensive) and add it to your payment.. I'm a Broker here in Scottsdale AZ and I only lend in Arizona. If you or someone you know is looking for financing options, feel free to contact me or pass along my information. William J. Acres, Lender411's number ONE lender in Arizona. 480-287-5714 WilliamAcres.com NMLS# 226347