<prompt> Human: My dad received a letter from the IRS telling him he owes roughly 4,500 in taxes due to a new employer submitting that he worked for them. The problem is my dad never worked at the company the IRS is telling us he worked at. I called the company in the letter and they basically told me they couldnt help us and to contact the IRS. What are the steps we should take here? We are definitely going to challenge this as this is incorrect, but do we have to file for identity theft? Or anything else? We live in California if that makes a difference.  <response>: Was the phone number provided on the notice a legit IRS phone number? Make sure hes not being scammed. 