Bad service Rendered

I reported my cv joint that broke off while driving then first contact was Nedbank as I have warranty plan with them and I explained the situation that I did not hit anything on the road it just snapped. Now my claim is rejected because they say it is an accident and I could have hit something meaning I **** and the way their contact centre agent Mpho spoke to me was suggesting that im lying and trying my luck. They have sent me up and down and putting me on hold for more than 10 to 15minutes and waste my airtime. I'm pretty sure there is a better way this couldhave been handled by innovations group