use strict;
use warnings;
use Data::Dump::Streamer;

my ($first, $second) = MySub();
my %hf = %{$first};
my %hs = %{$second};

Dump (\%hf, \%hs);


sub MySub {
    return ({1, 1, 2, 2}, {5, 5, 6, 6});
}
[download]

Prints:

$HASH1 = {
           1 => 1,
           2 => 2
         };
$HASH2 = {
           5 => 5,
           6 => 6
         };
[download]

as expected. How is your code different?