Asking for help regarding a

I was involved in an accident two years ago when I drove a U-Haul. I bought insurance and sent all the documents to the insurance company immediately. The U-Haul guy told me the insurance company would handle this. I have almost forgot this issue if I had not received a letter from that insurance company yesterday. I was asked to provided my auto insurance provider. I am very strange why they ask me for that after two years. And I have changed my auto insurance provider last year. My current auto insurance company should not be responsible for this accident happened two years ago. I'm very upset about this. I don't know what to do. Anyone has such experience, please give me advise. Thanks a lot!!!