You can find the CP or LTR number on the right corner of the letter. Letter 6475 helps EIP recipients determine if they're eligible to claim the Recovery Rebate Credit on their 2021 tax year returns.Fill out the MI-1040, lines 1-10. STOP. 3. This session covers the process of preparing and submitting proposals using the eResearch Proposal Management (eRPM) system. If you have trouble understanding the notice or how to respond to it, you should contact legal counsel or a tax clinic as soon as possible. What this letter is about. This is a fillable form – we recommend you type your information on lines 1a, 1b (you must include your full SSN or ITIN) and line 3. Then fill them out and mail them to the appropriate address listed below. Most taxpayers may request that their income tax refund be directly deposited into a U.S. financial account of their choice. See What is backup withholding, later.