The first hash in your array has duplicate keys. That's why you can't get to the value of the first key - it has already been overwritten. Dump the structure to see this.

my $json = '{

   "required": [
        {
            "docs": [
                {
                    "sec": "11111",
                    "number": "1"
                }
            ],
            "docs": [
                {
                    "sec": "22222",
                    "number": "2"
                }
            ],
            "name": "Mary Lou"
        },
    ...
}';
[download]

It seems strange that the value of "docs" in the quoted code should be an array with a single hash element. Was the original intention to make this an array of hashes? The posted code for printing the decoded JSON suggests this. Making this change to the JSON string produces the desired output with the posted code:

Win8 Strawberry 5.8.9.5 (32)  Mon 10/04/2021 20:14:50
C:\@Work\Perl\monks
>perl
use strict;
use warnings;

use JSON;

use Data::Dumper;

my $json = '{
   "required": [
        {
            "docs": [
                {
                    "sec": "11111",
                    "number": "1"
                },
                {
                    "sec": "22222",
                    "number": "2"
                }
            ],
            "name": "Mary Lou"
        },
        {
            "docs": [
                {
                    "sec": "33333",
                    "number": "1"
                }
            ],
            "name": "John De"
        },
        {
            "docs": [
                {
                    "sec": "4444",
                    "number": "1"
                }
            ],
            "name": "Smith Doe"
        },
        {
            "name": "Joseph D."
        }
    ]
}';

my $json_data = JSON->new;
my $data = $json_data->decode($json);

for my $dta ( @{ $data->{ required } || [] }) {
    if (scalar @{ $dta->{ docs } || [] } ) {
        for my $doc_data (@{ $dta->{ docs } || [] }) {
            if ($doc_data->{'sec'}) {
                print "\n Yes: $dta->{'name'} - $doc_data->{'sec'} ",
                      "| $doc_data->{'number'} \n";
                }
            }
        }
    else {
        warn "\n No sec value, just the name: $dta->{'name'} \n\n";
        }
    }
^Z

 Yes: Mary Lou - 11111 | 1

 Yes: Mary Lou - 22222 | 2

 Yes: John De - 33333 | 1

 Yes: Smith Doe - 4444 | 1

 No sec value, just the name: Joseph D.
[download]

I suspect that AnomalousMonk has given the correct answer to your previous post (Looping through an array) as well. Because there was nothing obviously wrong with that data (except for the translation from JSON to perl) , we assumed that your problem was with the code.
Bill

This particular AnoMonk has a ten year history here: see super search!

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery}

Please see

Does JSON syntax allow duplicate keys in an object?

• The short answer: Yes but is not recommended.
• The long answer: It depends on what you call valid...

So your options are:

• If you are the author of that JSON structure, please correct it.
• Otherwise it's pretty unclear how the result after conversion should look like, since Perl definitely doesn't allow (well overwrites) duplicated keys.
• If you are stuck with that format you can try to fiddle a solution with another module like JSON::Parse (see "SEE ALSO"), good luck!