Why do you turn warnings off? They would've told you

Variable "$client" will not stay shared at Op.pm line 59.

In Perl, nesting named subs doesn't make sense. Named subs exist in the namespace of the enclosing package, block scope doesn't influence them. It also means the closure is created around the $client variable from the first invocation of the outer sub.

But you should fix all the remaining problems, too.

Can't declare array dereference in "my" at Op.pm line 56, near "$respo
+nsalter;"
Global symbol "$target" requires explicit package name (did you forget
+ to declare "my $target"?) at Op.pm line 67.
Global symbol "$strExcelFilename" requires explicit package name (did 
+you forget to declare "my $strExcelFilename"?) at Op.pm line 85.
Global symbol "%header1" requires explicit package name (did you forge
+t to declare "my %header1"?) at Op.pm line 87.
Global symbol "@responsalter" requires explicit package name (did you 
+forget to declare "my @responsalter"?) at Op.pm line 94.
Global symbol "@responsalter" requires explicit package name (did you 
+forget to declare "my @responsalter"?) at Op.pm line 98.
Global symbol "$from_address" requires explicit package name (did you 
+forget to declare "my $from_address"?) at Op.pm line 112.
Global symbol "$to_address" requires explicit package name (did you fo
+rget to declare "my $to_address"?) at Op.pm line 113.
Global symbol "$subject" requires explicit package name (did you forge
+t to declare "my $subject"?) at Op.pm line 114.
Global symbol "$my_file_zip" requires explicit package name (did you f
+orget to declare "my $my_file_zip"?) at Op.pm line 121.
Global symbol "$your_file_zip" requires explicit package name (did you
+ forget to declare "my $your_file_zip"?) at Op.pm line 122.
Global symbol "$your_file_zip" requires explicit package name (did you
+ forget to declare "my $your_file_zip"?) at Op.pm line 124.
Global symbol "$mail_host" requires explicit package name (did you for
+get to declare "my $mail_host"?) at Op.pm line 126.
Global symbol "$from_address" requires explicit package name (did you 
+forget to declare "my $from_address"?) at Op.pm line 126.
Global symbol "$pass" requires explicit package name (did you forget t
+o declare "my $pass"?) at Op.pm line 126.
Execution of Op.pm aborted due to compilation errors.
[download]

I have fixed all compilation error now. There are the tokens and other base urls reading from the config.properties. Please suggest if anything wrong.

#!/usr/bin/env perl
package Op;
use strict;
use warnings;
use Win32::Process;
use REST::Client;
use JSON::Parse ':all';
use MIME::Base64;
use Term::ReadKey;
use Data::Dumper;
use MIME::Lite;
use Net::SMTP;
use Spreadsheet::XLSX;
use Spreadsheet::ParseXLSX;
use Excel::Writer::XLSX;
use Config::Properties;
use Data::Dumper;
use List::Compare;
use Array::Compare;
use Storable qw/freeze/;
use Data::Validate::IP;
use Data::Table::Excel;
use Excel::Writer::XLSX::Chart;
use Win32::OLE::Const; 
use Spreadsheet::WriteExcel::Utility qw( xl_range_formula );
use Win32::OLE;
use POSIX 'strftime';
use POSIX qw(strftime);
use DateTime;
use DateTime::Format::Strptime;
use Try::Tiny;
use feature qw{ say };

open my $fh, '<', "C:/PERL/" . "config.properties" or die "unable to o
+pen configuration file";
my $properties = Config::Properties->new();
$properties->load($fh);
my $value = $properties->getProperty('dev.token');
my $baseurl = $properties->getProperty('dev.baseURL');
my $from_address = 'chandan@aol.com';
my $to_address = 'chandan@bol.com';
my $subject = 'A message with 2 parts ...';
my $my_file_zip = 'C://PERL//';
my $mail_host = 'mail.aol.com';
my $pass = '1234567';



sub result {
    
    my ($args) = @_;
    my $appID   = $args->{APPID};
    my $datver   = $args->{datetime};
    my $email   = $args->{Email};
    my $date = strftime '%Y-%m-%d-%H-%M-%S', localtime;
    my $date3 = strftime '%Y-%m-%d' , localtime(time() - $datver*60*60
+);
    my $date4 = strftime '%Y-%m-%d' , localtime(time() - 24*60*60);
    my $apiurllog = $baseurl ."/users/sys/logs?";
    my $client = REST::Client->new();
    my @responsetext;
    my @responsetextall;
    my $sortor = "filter=eventType+eq+%22";
    my $filter = "all.auth.sso";
    my @responsalter;
    my $target = "%22+and+to.id+eq+%22";
    my $strExcelFilename;
    my %header1 = (
             -size => 10,
        );
    
    sub api_call {
  $client->addHeader('Authorization',"SSWS $value");
  $client->addHeader('Accept','application/json');
  $client->addHeader('Content-type','application/json');
  $client->GET($_[0]);
}

my $date2 = "%22&since=" . $date3 . "T00%3A00%3A00.000-04%3A00&until="
+ . $date4 . "T23%3A59%3A59.000-04%3A00";

my $urlstringlog = $apiurllog . $sortor . $filter . $target . $appID .
+ $date2;

$strExcelFilename = "C:/PERL/" . "My-File" . $date . ".xlsx";

my $your_file_zip = "My-File . $date . '.xlsx'";

run_api_call($urlstringlog);
@responsetext = parse_json ($client->responseContent());
push @responsetextall, @responsetext;

for my $i (0..$#responsetextall) {

for my $j (0..$#{$responsetextall[$i]}) {

 my $responseid = $responsetextall[$i][$j]{act}{UID};
 my $responsdisp = $responsetextall[$i][$j]{act}{Name};

push @responsalter,  $responseid ;
}

}

my $workbook  = Excel::Writer::XLSX->new( $strExcelFilename );
my $format_bold = $workbook->add_format( bold => 1, size => 10, top=> 
+1, bottom=> 1 ); 
        my $format2 = $workbook->add_format(%header1);
my $worksheet = $workbook->add_worksheet('UserSSO-Data');

my $r = 1;
my $r2 = 1;
my $r3 = 1;

 foreach my $j (0..$#responsalter ) {
            
                                $worksheet->write(0, 0, 'UserSSO-Total
+-Users' );
                                
            $worksheet->write($r2, 0, $responsalter[$j]);
            
        
            $r2 += 1;
        }
        
        
        
        $workbook->close;
print "Spreadsheet saved.\n";

## Mail Functionality

 my $msg = MIME::Lite->new (
   From => $from_address,
   To => $to_address,
   Subject => $subject,
   Type =>'multipart/mixed'
 ) or die "Error creating multipart container: $!\n";

$msg->attach (
    Type => 'text/csv',
    Encoding => 'base64',
    Path => $my_file_zip,
    Filename => $your_file_zip,
    Disposition => 'attachment'
 ) or die "Error adding $your_file_zip: $!\n";

 MIME::Lite->send('smtp', $mail_host, Timeout=>60,Auth=>'LOGIN',AuthUs
+er=>$from_address,AuthPass=>$pass,Port => 25, Debug => 1);
 
 }
                
__PACKAGE__
[download]

I am getting below error now

Undefined subroutine &Op::run_api_call called at C:/Users/chandan/Docu
+ments/Perl/webapp/bin/../lib/Op1.pm line 86.
C:/Users/chandan/Documents/Perl/webapp/bin/../lib/Op1.pm line 86
81    
82    $strExcelFilename = "C:/PERL/" . "My-File" . $date . ".xlsx";
83    
84    my $your_file_zip = "My-File . $date . '.xlsx'";
85    
86    run_api_call($urlstringlog);
87    @responsetext = parse_json ($client->responseContent());
88    push @responsetextall, @responsetext;
89    
90    for my $i (0..$#responsetextall) {
[download]

You removed sub result. Your code doesn't contain the nested subs anymore, but now you can't run the sub you need. Was it the right solution?

Take a step back. Start from a simple thing. Add one feature at a time, always test it didn't break. If you change several things at once, you don't know exactly which one is the culprit. For example, start with an empty page. Then add a form. Once it works, add calling the rest client. Once it works, add the spreadsheet. It's not a weakness to progress in small steps, it's a method that one needs to learn. You'll see it leads to the results faster than trying to write everything at once, in the end.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]