National Warranty Insurance Company Not honoring contract, time wasting, ripoff artists fraud Lincoln Nebraska

I purchase an extended auto warranty for a 1995 Dodge Ram from the dealership I bought the car from 20 months ago.The warranty cost just under $2000.I had driven 18000 miles in the vehicle and the engine failed, 2 weeks ago. I provided oil change receipts (5)to the warranty company, to cover the time I owned the vehicle, to show that I had been taking care of it.

The vehicle has been at the garage where it was towed to for 2 weeks now, with its engine hanging out. The warranty company said they wanted an oil sample 4 days ago, said there was carbon deposits inside the engine and, today, declined to fix my vehicle stating that the engine failed to to lack of proper maintenance lack of lube.

I have provided documentation to show that I have carried out more than the 1995 Dodge Ram Owners Manual recommends. How can I make them honor the contract?
My wife has had her car with the same warranty company for 3 years (It just expired) and we never needed to use it except for a new alternator. I thought they were a good company until now.

Vincent
Las vegas, Nevada
U.S.A.