See my similar code below and it's output from dumping the data. Give us a large sample of your code and run a dump using Data::Dumper or a similar module to show us the data structure generated. You'll be able to get a little more help then.

my %HOH;
$HOH{parent}{child1} = 'value1';
push @{ $HOH{parent}{child2} }, 'value2';
push @{ $HOH{parent}{child2} }, 'value3';


###
output:
{
  parent => { 
    child1 => "value1",
    child2 => ["value2", "value3"] },
}
[download]

My preference is the Data::Dump module used as below for your hash.

use Data::Dump qw(pp);
say pp(\%HOH);
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