No Answer from the call centre

Tried calling Avis fleet to enquire a simple query on my AVIS Optimum maintenance plan and held on for a total of 5 minutes on 2 calls with no option to leave my number for a call back. In addition there was no voice prompt advising that the call center is inundated with calls which leads me to believe that my call was simply ignored. Very poor service indeed. Can someone who cares at AVIS please call me back, my query is really very simple, its unfortunate that its led to a complaint because wat I was asking wouldnt have even taken 5 minutes had someone picked up my call initially.