I'm trying to only print the occurrence once

Not sure what you are trying to do. If you want to stop multiple records then just use a %seen{key} hash e.g.

#!perl
use strict;

my %seen = ();
while ( my $line = <DATA> ) {
  next if $line =~ /Insufficent|CLEARED/;
  if ( $line =~ /SNMP/ ) {
    my @f = split /\|/, $line; 
    my $node_ip = $f[4] || 'N/A';
    my $message = $f[13];
    my (undef,$ne) = split /[ &]+/,$f[15];
    
    unless ( $seen{$ne}++ ){
      printf "%-15s | %9s | %s \n", $node_ip, $ne, $message;
    }
  }
}
  
__DATA__
143599203|No|NACK|ENA||Major|20180129054027||ARM|NSA|PRM|0|DCN|Insuffi
+cient SNMP security settings|HN408-CP-1E-I|3176 && 1234|||||||No||
143599356|No|NACK|ENA|192.168.0.1|Major|20180129054037||CLR|NSA|PRM|0|
+DCN|CLEARED: Network element does not respond to SNMP requests|HN4000
+e|3176 && 12345|||||||No||
143599357|No|NACK|ENA|192.168.0.2|Major|20180129054039||CLR|NSA|PRM|0|
+DCN|CLEARED: Insufficient SNMP security settings|HN4000e|3176 && 1234
+56|||||||No||
143599999|No|NACK|ENA|192.168.0.3|Major|20180129054529||ARM|NSA|PRM|0|
+DCN|Network element does not respond to SNMP requests|HN4000e|3176 &&
+ 7890|||||||No||
143599999|No|NACK|ENA|192.168.0.3|Major|20180129054529||ARM|NSA|PRM|0|
+DCN|Network element does not respond to SNMP requests|HN4000e|3176 &&
+ 7890|||||||No||
143599999|No|NACK|ENA|192.168.0.3|Major|20180129054529||ARM|NSA|PRM|0|
+DCN|Network element does not respond to SNMP requests|HN4000e|3176 &&
+ 7890|||||||No||

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poj

In reply to Re^3: Print Max Hash by poj
in thread Print Max Hash by bartrad

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