I'm a victim of traffic accident pls help me with repair

I recently had a car accident where I was the victim. My car's bumper and fender were damaged, and today I visited the garage assigned by the insurance company.

The garage informed me that, according to the insurance policy, because my car is 6 years old, they cannot replace the bumper with a brand-new one, but only with a used part.

Is this a common practice in the UAE? In my home country, Victims can choose their preferred repair shop, even the official agency, and the parts are always replaced with brand-new ones.

I’m curious if this is standard practice here. If not, Can I dispute their POLICY?