I received a 1042-S in the mail. It is "Foreign Persons US Source Income Subject to Withholding". I am not sure what I am supposed to do with it, or if amend my taxes.

I received a 1042-S in the mail. It is "Foreign Persons US Source Income Subject to Withholding". I am not sure what I am supposed to do with it, or if I need to amend my taxes with this form. The income it shows is $968 which I am uncertain where it comes from.