Hi thanos1983 Thank you for your help, I extended your solution to check for these fields CF and ODB fields which I output to a comma separated file when set and not set. It works fine except for CF fields, I think this is because these lines are not unique in the file. For CF lines example I would like to set CfuNotSet if the line CFU-ALL-PROV-NONE is not found, CFbNoSet if the line CFB-ALL-PROV-NONE is not found and so on. Eventually I would also like to check for CB fields. I have done this without a hash with the help from Laurent_R but I would like to learn your solution too

This piece of code seems ok code

 
#build up the hash CF
    if (/CF/){
        
       $hash{CF} = $tmp[1];
        #say $hash{CF};
   }
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I think the problem is here

   #PROBLEM CODE check CF fields need to accommodate for multiple CF l
+ines 
   if (exists $hash{CF})
   {
   
          $add = $hash{CF};
         $line .= ",$add";
       
   }
[download]

<BEGINFILE>
<SUBBEGIN
    IMSI=11111111111111;
    MSISDN=431234567893;
    CB=BAOC-ALL-PROV;
    CB=BOIC-ALL-PROV;
    CB=BOICEXHC-ALL-PROV;
    CB=BICROAM-ALL-PROV;
    IMEISV=4565676567576576;
    CW=CW-ALL-PROV;
    CF=CFU-ALL-PROV-NONE-YES-NO-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-NO
+-NO-NO;
    CF=CFB-ALL-PROV-NONE-YES-YES-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-N
+O-NO-NO;
    CF=CFNRY-ALL-PROV-NONE-YES-YES-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO
+-NO-NO-NO;
    CF=CFNRC-ALL-PROV-NONE-YES-NO-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-
+NO-NO-NO;
    CF=CFD-TS10-ACT-91436903000-YES-YES-25-YES-65535-YES-YES-NO-NO-NO-
+YES-YES-YES-YES-NO;    
    ODBIC=BAIC;
    ODBOC=BAOC;
    ODBROAM=ODBOHC;
    ODBPRC=ENTER;
    ODBPRC=INFO;
    ODBPLMN=NONE;
    ODBPOS=NOBPOS-BOTH;
    ODBECT=OdbAllECT;
    ODBDECT=YES;
    ODBMECT=YES;
    ODBPREMSMS=YES;
    ODBADULTSMS=YES;
<SUBEND
<SUBBEGIN
    IMSI=11111111111133;
    MSISDN=431234567899;
    CB=BAOC-ALL-PROV;
    CB=BOIC-ALL-PROV;
    CB=BOICEXHC-ALL-PROV;
    CB=BICROAM-ALL-PROV;
    CW=CW-ALL-PROV;
    CF=CFU-ALL-PROV-NONE-YES-NO-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-NO
+-NO-NO;
    CF=CFB-ALL-PROV-NONE-YES-YES-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-N
+O-NO-NO;
    CF=CFNRY-ALL-PROV-NONE-YES-YES-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO
+-NO-NO-NO;
    CF=CFNRC-ALL-PROV-NONE-YES-NO-NONE-YES-65535-NO-NO-NO-NO-NO-NO-NO-
+NO-NO-NO;
    CF=CFU-TS10-ACT-914369050045021-YES-NO-NONE-YES-65535-YES-YES-NO-N
+O-NO-NO-NO-NO-NO-NO;
    CF=CFD-TS10-REG-91436903000-YES-YES-25-YES-65535-YES-YES-NO-NO-NO-
+YES-YES-YES-YES-NO;
    ODBIC=BICCROSSDOMESTIC;
    ODBOC=BAOC;
    ODBROAM=ODBOH;
    ODBPRC=INFO;
    ODBPLMN=PLMN1
    ODBPLMN=PLMN3;
    ODBPOS=NOBPOS-BOTH;
    ODBECT=OdbAllECT;
    ODBDECT=YES;
    ODBMECT=YES;
    ODBPREMSMS=NO;
    ODBADULTSMS=YES;
<SUBEND
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If I understand it correctly you split up the lines of the record based on the equals sign. This seems to work fine until CF entries are encountered

#!/usr/bin/perl
use strict;
use warnings;
use feature 'say';
use Data::Dumper;

my $HSSIN='D:\testproject\HSS-export.txt';
my $ofile = 'D:\testproject\HSS-output-withhash.txt';
open (INFILE, $HSSIN) or die "Can't open input file";
open (OUTFILE,"> $ofile" ) or die "Cant open file"; 


my %hash;
my $count = 0;
my $add;
my $line;
while (<INFILE>) {
    chomp;
    next if /^<ENDFILE>/;
    next if /^<BEGINFILE>/;
    if (/<SUBBEGIN/) {
    $count = 1;
    }
    elsif (/<SUBEND/) {
    $count = 0;
    }
    elsif ($count) {
    my @tmp = split /=/;
    chop $tmp[1];
   
    #build up the hash CF
    if (/CF/){
        
       $hash{CF} = $tmp[1];
        #say $hash{CF};
   }
    
    if (/MSISDN/) {
        $hash{MSISDN} = $tmp[1];
      
    }
    if (/ODBIC/) {
        $hash{ODBIC} = $tmp[1];
    }
    elsif (/ODBOC/) {
        $hash{ODBOC} = $tmp[1];
    }
    elsif (/ODBROAM/) {
        $hash{ODBROAM} = $tmp[1];
    }
    }
    
    if ($count == 0) {
    #check MSISDN field 
    if (exists $hash{MSISDN}) 
    {
               
        $line = $hash{MSISDN};
        #'say OUTFILE $line;
        #say OUTFILE "Update Command <".$hash{MSISDN}.">,".$hash{ODBIC
+}.",".$hash{ODBOC}.",".$hash{ODBROAM}."";
    }
    else 
    {
       #say OUTFILE "Update Command MSISDN=notSet,".$hash{ODBIC}.",".$
+hash{ODBOC}."";
       $line = 'MSISDN=notSet';     
    }
    
    
   #PROBLEM CODE check CF fields need to accommodate for multiple CF l
+ines 
   if (exists $hash{CF})
   {
   
          $add = $hash{CF};
         $line .= ",$add";
       
   } 
       
   #check ODBIC field
   if (exists $hash{ODBIC})
   {
          $add = $hash{ODBIC};
          $line .= ",$add";
         
       
   }
   else 
   {
           $add = 'ODBICnotSet';
           $line .= ",$add";
   }
   
   #check ODBOC field
   if (exists $hash{ODBOC})
   {
          $add = $hash{ODBOC};
          $line .= ",$add";
       
   }
   else 
   {
           $add = 'ODBOC notSet';
           $line .= ",$add";
   }
 
  #check ODBROAM field 
  if (exists $hash{ODBROAM})
   {
          $add = $hash{ODBROAM};
          $line .= ",$add";
       
   }
   else 
   {
           $add = 'ODBROAM notSet';
           $line .= ",$add";
   }

#check hash for ODBOC->BAOC is not set set it to ODBOC->BAOCnotSet 
    delete $hash{MSISDN};
    delete $hash{ODBIC};
    delete $hash{ODBOC};
    delete $hash{ODBROAM};
    delete $hash{CF};


#build up line 
say OUTFILE $line;
    
 }

}

close INFILE;
close OUTFILE;
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