different results in numFound vs using the cursor

[rhys J]

i am using this logic in perl:

my $decoded = decode_json( $solrResponse->{_content} );
my $numFound = $decoded->{response}{numFound};

$cursor = "*";
$prevCursor = '';

while ( $prevCursor ne $cursor )
{
  my $solrURI = "\"http://[SOLR URL]:8983/solr/";
  $solrURI .= $fdat{core};

  $solrSort = ( $fdat{core} eq 'dbtr' ) ? "debtor_id+asc" : "id+asc";
  $solrOptions = "/select?indent=on&rows=$getrows&sort=$solrSort&q=";
  $solrURI .= $solrOptions;
  $solrURI .= $query;

 $solrURI .= ( $prevCursor eq '' ) ? "&cursorMark=*\"":
                     "&cursorMark=$cursor\"";

 print STDERR "solrURI '$solrURI'\n";
 my $solrResponse = $ua->post( $solrURI );
   my $decoded = decode_json( $solrResponse->{_content} );
  my $numFound = $decoded->{response}{numFound};

 foreach my $d ( $decoded->{response}{docs} )
  {
      my @docs = @$d;
      print STDERR "size of docs '" . scalar( @docs ) . "'\n";
   foreach my $r ( @docs )
           {
               if ( $fdat{cust_num} and $fdat{core} eq 'dbtr' )
               {
                   push ( @solrResults, $r->{debtor_id} );
               }
               elsif ( $fdat{cust_num} and $fdat{core} eq 'debt' )
               {
                   push ( @solrResults, $r->{debt_id} );
               }
           }

}
   $prevCursor = ( $prevCursor eq '' ) ? "*" : $cursor;
 $cursor = $decoded->{nextCursorMark};
  print STDERR "cursor '$cursor'\n";
  print STDERR "prevCursor '$prevCursor'\n";
  print STDERR "size of solrResults '" . scalar( @solrResults ) . "'\n";
}

print out:

http://[SOLR
URL]:8983/solr/debt/select?indent=on&rows=1000&sort=id+asc&q=debt_id:
608384 OR debt_id: 393291&cursorMark=AoEmMzkzMjkx

The numFound: 35008
final size of solrResults: 22006

Am I missing something I should be using with cursorMark? Or is this
expected?

I've checked my logic, and I'm using the cursors the way this page is using
them in examples:

https://lucene.apache.org/solr/guide/6_6/pagination-of-results.html

Thanks

Rhys