I think you need to declare the package name at the top like:

package Your::Package;
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Make sue they are in the appropriate directories too.

This is what i have at the top of my modules:

package My::Module;

use Exporter qw(import);
@EXPORT_OK = qw(sub names here);
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An example:

package My::Package;

use Exporter qw(import);
@EXPORT_OK = qw(print_lines);

use strict;
use warnings;

sub print_lines{
    
    my ($input) = @_;

    while(my $lines = <$input>){
        print $lines;
    }
}
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And call it from you script like:

use strict;
use warnings;

use My::Package qw(print_lines);

open my $file, '<', shift;

print_lines($file);
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