What is the $param returned for each 'type' key after the subroutine &return_param_name? I'd suggest you sprinkle some print statements around as follows and show what &return_param_name looks like,

 my $value = $q->{'content'};
            my $param = $q->{'type'};
            print $param,"$/";   #<------------------Here
            #$value =~ s/^\s+|\s*$//g;
            $param = &return_param_name($param);
            print $param,"$/"; #<--------------------Here
            push @{$qryhash{$param}}, $value;
[download]

Since your problem lays in converting an AoH to a HoA by iterating over the AoH, using the Dumped output you provided it is possible to iterate as follows:

#!/usr/local/bin/perl
#title "Problem iterating AoH"
use strict;
use warnings;

my @queries = (
        {
             'content'=>'Blocking',
             'type' => 'blocking'
             },
             {
              'content'=>'p01',
              'type'=>'Priority'
              }
      );


my %hash;
for my $reference (@queries){ 
    push @{$hash{$reference->{'type'}}},$reference->{'content'};
    }
    
use Data::Dumper;
print Dumper(\@queries),"\n";
print Dumper(\%hash);
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OUTPUT:

$VAR1 = [
          {
            'content' => 'Blocking',
            'type' => 'blocking'
          },
          {
            'content' => 'p01',
            'type' => 'Priority'
          }
        ];
$VAR1 = {
          'blocking' => [
                          'Blocking'
                        ],
          'Priority' => [
                          'p01'
                        ]
        };
[download]