1099-DIV received after a Decedent's final return

My Father passed away in 2020, a 1099-DIV form for $46 was received under his SSN in 2021

His estate is closed and his final tax return has been filed

The payee will not change the 1099-DIV form

As I understand it, this income should be included by his beneficiary

Question; 

1) How do I add the income on the beneficiary's tax return (include the dividend income with no 1099-DIV form received)?

2) Do I need to inform the IRS and if so, how?

Thanks!