Choice Home Warrant Authorizes amounts and then backs out of them Edison, New Jersey

We are a vendor for Choice Home warranty, we were authorized for a specific amount to fix plumbing in a homeowners house. When we submitted the bill to Choice they did not pay right away until I called and finally had to send them a collection letter. They made a partial payment and when I called them back they said they would have never authorized anything over $250.00 and they did not owe us any more money. I would advise other service providers to be very wary of this company. the person I have been dealing with is very rude and is not professional at all.