diff --git a/lib/data/models/task_model.dart b/lib/data/models/task_model.dart
index 2702f6a41..591e21fbc 100644
--- a/lib/data/models/task_model.dart
+++ b/lib/data/models/task_model.dart
@@ -138,6 +138,10 @@ abstract class TaskEntity extends Object
 
   int get duration;
 
+  bool get areTimesValid {
+    final times = taskTimes;
+  }
+
   List<TaskTime> get taskTimes {
     final List<TaskTime> details = [];
 
@@ -158,6 +162,8 @@ abstract class TaskEntity extends Object
       details.add(taskTime);
     });
 
+    details.sort((timeA, timeB) => timeA.startDate.compareTo(timeB.startDate));
+
     return details;
   }
 
diff --git a/lib/ui/task/edit/task_edit_times.dart b/lib/ui/task/edit/task_edit_times.dart
index 7d3d10ef2..1dabb4d11 100644
--- a/lib/ui/task/edit/task_edit_times.dart
+++ b/lib/ui/task/edit/task_edit_times.dart
@@ -199,8 +199,9 @@ class TimeEditDetailsState extends State<TimeEditDetails> {
               selectedDate: _startDate,
               onSelected: (timeOfDay) {
                 _startDate = timeOfDay;
-                _durationController.text =
-                    formatDuration(_endDate.difference(_startDate));
+                _durationController.text = _endDate != null
+                    ? formatDuration(_endDate.difference(_startDate))
+                    : '';
               },
             ),
             TimePicker(
@@ -209,8 +210,9 @@ class TimeEditDetailsState extends State<TimeEditDetails> {
               selectedDate: _endDate,
               onSelected: (timeOfDay) {
                 _endDate = timeOfDay;
-                _durationController.text =
-                    formatDuration(_endDate.difference(_startDate));
+                _durationController.text = _endDate != null
+                    ? formatDuration(_endDate.difference(_startDate))
+                    : '';
               },
             ),
             PopupMenuButton<int>(
diff --git a/lib/ui/task/edit/task_edit_vm.dart b/lib/ui/task/edit/task_edit_vm.dart
index cbf9540c8..390dba0d1 100644
--- a/lib/ui/task/edit/task_edit_vm.dart
+++ b/lib/ui/task/edit/task_edit_vm.dart
@@ -69,6 +69,8 @@ class TaskEditVM {
         store.dispatch(EditTaskTime(taskTime));
       },
       onSavePressed: (BuildContext context) {
+
+
         final Completer<TaskEntity> completer = new Completer<TaskEntity>();
         store.dispatch(SaveTaskRequest(completer: completer, task: task));
         return completer.future.then((savedTask) {