... detirmine the [most] recent dates from users

The date-timestamps are held in the anonymous array references that are the values of the key(s) of $hash{$id}{$net}. As suggested by choroba here, the particular format of these date-timestamps is easily sort-ed to determine temporal order: 

Win8 Strawberry 5.8.9.5 (32)  Sun 03/14/2021 21:56:16
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings

my %hash;

$hash{'ID'}{'NET'} = [ qw(
  2019-11-07T20:31:10.000Z  2021-03-10T13:58:50.000Z  2021-02-19T13:47
+:25.000Z
  ) ];

my $most_recent_date_time = (sort @{ $hash{'ID'}{'NET'} })[-1];
print "'$most_recent_date_time' \n";

^Z
'2021-03-10T13:58:50.000Z'

[download]
Try some other date-timestamps (with the identical format!) and convince yourself this is true.

(And congratulations on having had an almost-complete solution finally delivered into your hands! Please see the Offering Plate. :)

Give a man a fish:  <%-{-{-{-<

In reply to Re^5: How i can create hash of arrays of hashes from my 3 arrays? by AnomalousMonk
in thread How i can create hash of arrays of hashes from my 3 arrays? by chandantul

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