Poor customer service, Insurance and damage issue

I had insurance on my wheels and auto glass, lost a wheel cap and was charged R1220. Thrifty first just deducted the money from my credit card and then marked my dispute ticket as resolved without any agent getting back to me. When I phone them, the call drops after holding on 30 min. This is the worst experience I have had with car rental companies. Furthermore, wheel caps doesn't just fall off while driving and therefore shows the quality of vehicles they provide and I therefore can't help wondering whether that is how they make their money by just deducting random amounts from credit cards. I never received the invoice for the damage either.