American Residential Warranty review: service not provided as promised

I took the home warranty from the company in the beginning of June 2014. I noticed a minor leak in my kitchen sewer pipe leading to the main sewer line. I called the company on 7/31/2014. Some one from the company's affiliate in New York came to my house on 8/1/2014. I paid the representative $55.00 for the visit. I got a call from American Residential that it was a pre-existing condition. I told them if it was pre-existing condition then my basement could have flooded. After couple of E-Mails and telephone calls the company came out with another excuse telling that it was a corrosion, therefore it is not covered. It was a news to me that Cast Iron Sewer pipe gets corroded. I think the company is a fraud. Now they want another $20.00 for the diagnostic test. It is funny that the company does not want to pay for the repair and on top of that they want another $20.00. This kind of company should not exist in business. I was forced to cancel my policy immediately. Could some one really check the company and its reputation and take some action against this outfit.