Well they always ask to attach any supporting documents when we mail them in. I was just wondering how to do that. For instance, one of my clients brought me a 2019 w-2 form instead of a 2020. The government caught it and refused his refund. He had already received his state refund. So I had to do an amended return with the 2020 information. I thought I should attach the 2 w-2s to show what we were doing.
