Avis refuse to pay back 3rd party claim!

Avis car rental bumped into our tourism bus on N2 CPT on 13 Nov. They say there is no claim report and thus I can not claim as 3rd party. I have been waiting for almost 4 weeks and there is still no claim report from their side. This was clearly Avis car rental fault and I want my money for repairs. My tourism bus is damaged and could not operate for 3 weeks. Claims department and Stand branch blame each other. No service from Avis and they Ignore emails for weeks!