diff --git a/Koha/SearchEngine/Elasticsearch/Search.pm b/Koha/SearchEngine/Elasticsearch/Search.pm
index 07380207ce..1402a79edd 100644
--- a/Koha/SearchEngine/Elasticsearch/Search.pm
+++ b/Koha/SearchEngine/Elasticsearch/Search.pm
@@ -187,7 +187,7 @@ sub search_auth_compat {
             # rather than hard-coded conversions.
             # Our results often come through as nested arrays, to fix this
             # requires changes in catmandu.
-            my $authid = $record->{ 'local-number' }[0][0];
+            my $authid = $record->{ 'Local-number' }[0][0];
             $result{authid} = $authid;
 
             # TODO put all this info into the record at index time so we