HSA Home Warranty Warrranty Denied due to technician breaking furnace claiming it was already broken Nationwide

I got a home warranty when we purchased our house.  The furnace stopped working correctly called HSA they sent out a technician to diagnose the problem.  He was unprofessional and told me he needed time to diagnose the problem.  He then proceeded to tell me that a previous contractor is the one who broke the furnace.  Told warranty company furnace was missing pieces so claim denied.  My furnace would at least run for 10 minutes before he showed up and pieces were not broken now after he leaves I have broken plastic parts and the furnace will not even turn on.  I am not sure if they use very unethical companies to perform service or they are unethical themselves. It seems to be a bit of both.  Spent 75.00 for a service call so the tech can break my furnace, get claim denied and have to spend money on a new furnace.  i would not recommend this company.  ABSOLUTELY HORRIBLE.