eclipse PDT does not recognize the use command

Question

I'm using Eclipse Version: 2021-03 (4.19.0), and I'm getting syntax errors when trying to "use" namespaces.

Is there something I can do to fix this?

Example:

use PhpOffice\PhpSpreadsheet\Spreadsheet;

The PHP Parser recognizes "PhpOffice" as a syntax error on this line and others like it.

i'm using php version 7.4 and in the menu "eclipse->project->properties->PHP->validation" there is php 7.4