Extremely unhappy customer

Motorvaps is the worst extended warranty insurer. They don't value their customers and only care for their own interests. My recent claim was rejected and they fail to provide evidence of why they rejected it. The claim was for an electrical failure on the car's alternator and my repairer provided a report with the details. Motorvaps insists that its wear and tear but they can't provide proof of which part of the alternator has worn off. I have sent multiple emails requesting the evidence to confirm which part has worn off but they have not responded to my emails, not even an acknowledgement. They are happy take people's money but when it's time to deliver on their part they just go quiet.