I try to use Thread::Queue to send info, but when join this thread, it leads to a error " Free to wrong Pool", I followed some topics about this error, cannot find any reasonable explanation, except for use of win32::ole

our @Task_list;
our ($DataQueue1,$DataQueue2);
my $ExcelFile='D:\HF_project_perl\Update.xls';
#this use win32:ole to read excel 
@Task_list=Create_TaskList($ExcelFile);
print "Create TaskList";

#Create 2 Queues  $DataQueue1-- Main thread to thread1; #$DataQueue2--
+-therad1 to thread2 
$DataQueue1 = Thread::Queue->new();
$DataQueue2 = Thread::Queue->new();



my $thr1 = threads->create(\&thread1);
print "set up thread1 \n";#for debug

my $thr2 = threads->create(\&thread2);
print "set up thread2 \n"; #for debug


#Assign Task  to thread1  by $DataQueue1
for my $i (0..$#Task_list){
$DataQueue1->enqueue($Task_list[$i]);
print "send task $i to Thread1 \n"; #for debug
print "wait 10s \n";
sleep(10);


}

#Task completed Flag
$DataQueue1->enqueue(undef); 
print "send undef to stop T1 ";


$thr2->join();
$thr1->join();



sub thread1{
         
          my $TaskRef;
          my $Taskcounter;
          while ( defined($TaskRef = $DataQueue1->dequeue())) {

           $Taskcounter++;
           my $SecID=$TaskRef->{SecID};
           my $Date=$TaskRef->{Date};
        
           print "Thread1 finish task $Taskcounter";
           print "$SecID $Date \n";

           $DataQueue2->enqueue($TaskRef); 
# notify thread2 to follow the task, Assign Task to thead2 by $DataQue
+ue2
           
           print  "Send task $Taskcounter to T2 \n";#for debug
           
           print "T1 wait 2s \n";
           
           sleep(2);
        }      
        
        $DataQueue2->enqueue(undef);#Task completed Flag
        select(STDOUT);
        print "T1 stop and inform T2 to stop \n";  #for debug
    }


sub thread2{
                     
          
         my $TaskRef;
        my $Task_Finished_counter=0;
        while ( defined($TaskRef = $DataQueue2->dequeue()) ) {
       
          
          print  "Thread2 finish task $Task_Finished_counter";
          print "$TaskRef->{SecID} $TaskRef->{Date} \n"; #for debug
          
          
        }
            
         
     print "T2 stop \n"; #for debug     
          
    }
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a easy example for threads way, error "Free to wrong Pool" happens when join the thread , why ?