What if you’re receiving letters from an attorney about a case for car damage you’re aware of but you don't know the individual listed in the letter?

Turn it over to your auto insurance.

It does not matter whether you know the parties. If you are a witness to the accident and have some information to what you saw, that is why you are being contacted.

It really depends on what the letter says. For example, if the letter asks you to contact the attorney to discuss the matter, then perhaps you should do this. Even if you know nothing about the accident, at least the attorney would then know that you do not have relevant information. I the letter includes a subpoena to testifying court or a deposition, then you should appear at the court or deposition at the appropriate time or place.

you probably would be well off asking a lawyer to respond to take the pressure off you

If you had auto insurance when the accident occurred, you need to take the letter to your insurance agent at once. The fact that you do not recognize the name of the person the attorney is claiming to represent does not mean that that person does not have a claim. More importantly, failure to advise your insurance company of the claim may cause you to lose coverage for the claim and the insurance company may not have to represent you if a lawsuit is filed. If you had no insurance, see an attorney at once to see if you can work out something before your license is suspended.