} elsif ($attachment_filename && $self->{"${prefix}number"}) {
     $attachment_filename .=  "_" . $self->{"${prefix}number"} . $self->get_extension_for_format();
 
+  } elsif ($attachment_filename) {
+    $attachment_filename .=  $self->get_extension_for_format();
+
   } else {
     $attachment_filename = "";
   }
     if ( $selected_tax ) {
 
       if ( $buysell eq 'sell' ) {
-        $self->{AR_amounts}{"tax_$i"} = $selected_tax->chart->accno unless $selected_tax->taxkey == 0;
+        $self->{AR_amounts}{"tax_$i"} = $selected_tax->chart->accno if defined $selected_tax->chart;
       } else {
-        $self->{AP_amounts}{"tax_$i"} = $selected_tax->chart->accno unless $selected_tax->taxkey == 0;
+        $self->{AP_amounts}{"tax_$i"} = $selected_tax->chart->accno if defined $selected_tax->chart;
       };
 
       $self->{"taxkey_$i"} = $selected_tax->taxkey;