The data in the text file is the same as before. Nothing different. The error i get is.

bad data </home/vlr/archive/temp.txt> at ./vlr-cdma-test.pl line 32, <$fh> line 1.

These are my codes. #vlr-cdma-parse.pl

#!/usr/bin/perl -w
use strict;
use warnings;
use Text::ParseWords;

my $dir = "/home/vlr/archive/";

my $date = "20211201";
chomp($date);

# Check directory for relevant files
opendir(DIR, $dir) or die "Could not open ".$dir."\n";
my @dir = grep(/^USRINF.*.$date.*.1700.txt$/, readdir DIR);
closedir DIR;

my $file = $dir."temp.txt";

open my $FH, '>', $file;
foreach $_(sort @dir){
    my $DFile = $dir.$_;
    print "Processing: ".$DFile."\n";
    # Open Data File and parse each line
    open my $DF, '<', $DFile or die "Can't open $DFile $!";
    foreach $_ (<$DF>){
        chomp( $_ );
        if((length $_ > 0)&&($_ =~ /^\d{15}/)){
            $_ =~ s/\s+/;/g;
            my($imsi,$mdn,$sec) = (quotewords('[\t;]+|,\s', 0, $_))[0,
+1,3];
            if((($imsi =~ /^\d{15}/)&&($imsi =~ /^(702|310)/))&&(($mdn
+ =~ /^\d{10}/)&&($mdn =~ /^(501)/))){
                print $FH $imsi.",".$mdn.",".$sec."\n";
            }
        }
    }
    close $DF;
}
close $FH;
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Then I would like to call the text file with your code. #vlr-cdma-test.pl

#!/usr/bin/perl -w

use strict; # https://perlmonks.org/?node_id=11140267
use warnings;
use Data::Dumper qw(Dumper);

my $dir = "/home/vlr/archive/";
my $file = $dir."temp.txt";

open my $fh, '<', \$file or die; # FIXME change for your file
my $thirty = 1; # FIXME 1 for testing, should be 30
my (%answer, %lines);
$lines{ /,(.+)/ ? $1 : die "bad data <$_>" }++ while <$fh>;
for ( keys %lines )
  {
  my ($value, $key) = split ',';
  $lines{$_} > $thirty and push @{ $answer{$key} }, $value;
  }

open my $FH, '>', 'output.txt';
    print $FH Dumper(\%answer);
close $FH;
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