I have a 2021 1099-R issued as follows with the code PJ in Box 7. I assume this means that I have to amend 2020's return. With the following details, which figures should be added to Gross income in 2020 1040X? Is it Box 1 (1300) figure or Box 2a (200)?
Box 1. Gross Distribution 1300
Box 2a. Taxable 200
Box 4 Federal Tax Wh/H 20
Box 7 Code PJ
