diff --git a/modules/interventi/src/Components/Sessione.php b/modules/interventi/src/Components/Sessione.php
index a5b8912c2..9b4ceb688 100755
--- a/modules/interventi/src/Components/Sessione.php
+++ b/modules/interventi/src/Components/Sessione.php
@@ -53,7 +53,7 @@ class Sessione extends Model
     public static function build(Intervento $intervento, Anagrafica $anagrafica, $inizio, $fine)
     {
         if (!$anagrafica->isTipo('Tecnico')) {
-            throw new InvalidArgumentException();
+            throw new InvalidArgumentException("Anagrafica di tipo diverso da Tecnico");
         }
 
         $model = new static();
diff --git a/plugins/notes.php b/plugins/notes.php
index 1e945f917..6d2d1f128 100755
--- a/plugins/notes.php
+++ b/plugins/notes.php
@@ -19,7 +19,7 @@
 
 include_once __DIR__.'/../core.php';
 
-if (!$notes->isEmpty()) {
+if (!empty($notes) && !$notes->isEmpty()) {
     echo '
         <div class="box box-info direct-chat direct-chat-info">
             <div class="box-header with-border">