After you file

I deed to amend my 2019 Tax Return due to my own error, do I need an AMENDED FILE FORM? 

The original 2019 Tax Return was just mailed on 1/6/2021 

Since having to file by mail, I dont know if they have received it. 

They owe me more money.  So is there an 2019 tax return form I need to mail mail with the Amended tax return?