AVIS most terrible service ever

My vehicle is in for repairs. A rental vehicle was booked by my insurance Discovery Insure. Avis called at 10.20 AM to inform me that the rental vehicle will be ready by 11:00 AM delivered to my home. I am still waiting. I called the Main Call centre several times during today and kept hanging on for almost more than 20 mins for a response. Eventually when a consultant answers the phone and I explain the scenario they try from their side to connect with the PTA branch. No joy! Discovery finally got through to AVIS 20 mins ago only to let me know that the rental will be delivered tomorrow at 11. Between Discovery and AVIS car rental I don't know who is the worst. No communication - no excuse - no sorry at all. Although "all calls are being recorded"