diff --git a/modules/client/front/defaulter/index.html b/modules/client/front/defaulter/index.html
index cf880e0f7..3ea88088b 100644
--- a/modules/client/front/defaulter/index.html
+++ b/modules/client/front/defaulter/index.html
@@ -34,7 +34,7 @@
             </div>
             <div class="vn-pa-md">
                 <vn-button
-                    ng-show="$ctrl.checked.length > 0"
+                    disabled="$ctrl.checked.length == 0"
                     ng-click="notesDialog.show()"
                     name="notesDialog"
                     vn-tooltip="Add observation"
diff --git a/modules/client/front/defaulter/index.js b/modules/client/front/defaulter/index.js
index 920248547..292505c91 100644
--- a/modules/client/front/defaulter/index.js
+++ b/modules/client/front/defaulter/index.js
@@ -5,6 +5,7 @@ import UserError from 'core/lib/user-error';
 export default class Controller extends Section {
     constructor($element, $) {
         super($element, $);
+        this.defaulter = {};
         this.defaulters = [];
         this.checkedDefaulers = [];