Poor poor service

Hi all as we speak I am sitting at a dealer with my car having a service plan with genric insurance. They did not pay for service. They say the invoice did not arrive before 11. The manager said he can't do anything and I must write a complaint about the service. I am beyond embarrassed because the car is done and they not paying. Good luck to you who will still decide to go with them because they affordable. That is why we have monthly fees so that we don't have to make cash payments.