diff --git a/tools/automatic_item_modification_by_age.pl b/tools/automatic_item_modification_by_age.pl
index 8be74ee0cb..41f4013aa8 100755
--- a/tools/automatic_item_modification_by_age.pl
+++ b/tools/automatic_item_modification_by_age.pl
@@ -56,7 +56,14 @@ my ( $template, $loggedinuser, $cookie ) = get_template_and_user(
     }
 );
 
-my $op = $cgi->param('op') // 'show';
+my $op                 = $cgi->param('op') // 'show';
+my @item_fields        = map { "items.$_" } Koha::Items->columns;
+my @biblioitem_fields  = map { "biblioitems.$_" } Koha::Biblioitems->columns;
+my @biblio_fields      = map { "biblio.$_" } Koha::Biblios->columns;
+my @allowed_age_fields = (
+    'items.dateaccessioned', 'items.replacementpricedate', 'items.datelastborrowed', 'items.datelastseen',
+    'items.damaged_on',      'items.itemlost_on',          'items.withdrawn_on'
+);
 
 my $syspref_name = q|automatic_item_modification_by_age_configuration|;
 if ( $op eq 'cud-update' ) {
@@ -89,6 +96,7 @@ if ( $op eq 'cud-update' ) {
         $rule->{age} = $cgi->param("age_$unique_id");
 
         for my $age_field (@age_fields) {
+            next unless grep { $_ eq $age_field } @allowed_age_fields;
             $rule->{agefield} = $age_field ? $age_field : "items.dateaccessioned";
         }
         push @rules, $rule;
@@ -114,17 +122,10 @@ if ($@) {
     exit;
 }
 
-my @item_fields       = map { "items.$_" } Koha::Items->columns;
-my @biblioitem_fields = map { "biblioitems.$_" } Koha::Biblioitems->columns;
-my @biblio_fields     = map { "biblio.$_" } Koha::Biblios->columns;
-my @age_fields        = (
-    'items.dateaccessioned', 'items.replacementpricedate', 'items.datelastborrowed', 'items.datelastseen',
-    'items.damaged_on',      'items.itemlost_on',          'items.withdrawn_on'
-);
 $template->param(
     op                  => $op,
     messages            => \@messages,
-    agefields           => [@age_fields],
+    agefields           => [@allowed_age_fields],
     condition_fields    => [ @item_fields, @biblioitem_fields, @biblio_fields ],
     substitution_fields => \@item_fields,
     rules               => $rules,