Credit collection Services commercial CCSC Subrogation notice Norwood Massachusetts

I was sent a letter stating that I needed to provide insurance coverage for an incident which, did not accure (I was at work),it says that their client will sue for damages for an auto accident that I was not in. My insurance definitely would have notified me. And my car has no accident damage. I was also threatened with loss of license if I didn't pay a sum amount of $4,000. And this was regarding through Allstate insurance company which my personal insurance company has not notified me about anything because again I was not in an accident I was at work! this is definitely a fraud!