That is definitely a disaster if you don't inform your insurance company. Indeed, you should have to inform your insurance provider as soon as possible. Otherwise, your insurance claim will be rejected for that accident.
In this regard, I usually get the best advice from this site
https://www.multiquotetime.com/ whether it is about minibus, car, business, or property insurance. According to them, it is significant to notify your insurance agent about an accident within 24 to 72 hours after the misadventure. Therefore, you need to share details like accident timing, location, damage, and injury with your insurance agent.
You should involve your lawyer in case of any injury or bad collision.