while you are supposed to amend consider how much income is involved before doing so.
if you decide to amend look at the year on the 1099. in theory, it should be for 2019, not the year cashed. if it's for the year cashed you report on 1099-INT and then enter the same amount as an adjustment "US savings bond interest previously reported". this is so you don't get taxed on the same income twice. schedule B for the year cashed would show the 1099 amount and a subtraction labeled as such.
