Teilnahmerechnungen erstellen

app/Models/Event.php

@@ -45,6 +45,7 @@ use Illuminate\Database\Eloquent\Relations\HasMany;
  * @property float $support_flat
  * @property int $alcoholics_age
  * @property boolean $archived
+ * @property string|null $invoice_key
  */
 class Event extends InstancedModel
 {
@@ -90,6 +91,7 @@ class Event extends InstancedModel
         'participation_options',
         'addons',
 
+        'invoice_key',
     ];
 
     protected $casts = [