I am so sorry to hear about the damage to your home. I can only imagine how distressing this must be for you to take care of from afar. I have escalated your comments and a claims specialist should be reaching out to you. Thank you for posting here in the community.
You pay insurance to protected against "covered" loss. It is your responsibly to read and understand your policy to ensure that it contains all the coverage you want and/or need.
Flood insurance has never been part of the homeowners policy and usually is not required (by the bank holding mortgage) unless the home is in a designated flood zone. As you have found out flooding can happen in areas not designated as a flood zone. Most people don't take the coverage unless they are required, to save money. Don't forget coverage for earthquakes!