Perhaps you can adapt this to exactly what you need

#!perl
use strict;
use SOAP::Lite; 

my $uri    = 'https://login.swift-kanban.com/axis2/services/KanbanCard
+Service?wsdl';
my $proxy  = 'https://login.swift-kanban.com/axis2/services/KanbanCard
+Service';
my $client = SOAP::Lite->uri($uri)
                       ->proxy("loopback://");
$client->autotype(0);
$client->outputxml(1);
$client->readable(1);
$client->ns($uri,'kan');
$client->envprefix('soapenv');

my %value = (
  'name'           => 'teste de criacno',
  'cardSize'       => 'M',
  'classOfService' => 'Expedite'
);

my @fields;
for my $field (sort keys %value){
  push @fields,SOAP::Data->name( "field"=> $value{$field} )
          ->attr( {'name'=>$field} )
          ->prefix('kan');
};

my %data = (
  projectId   => 'PROJECTID',
  cardType    => 'CARDTYPE',
  userLoginId => 'USERLOGINID',
  fields      => \@fields,
);
my @data;
my @keys = qw(projectId cardType userLoginId fields);
for (@keys){
  push @data,SOAP::Data->name($_ => $data{$_})->prefix('kan')
}

my $response = $client->call('addCardDetails',@data);    
print $response;
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