diff --git a/app/src/main/java/fr/gouv/etalab/mastodon/activities/InstanceHealthActivity.java b/app/src/main/java/fr/gouv/etalab/mastodon/activities/InstanceHealthActivity.java
index 302a49aa8..2ce90ae2f 100644
--- a/app/src/main/java/fr/gouv/etalab/mastodon/activities/InstanceHealthActivity.java
+++ b/app/src/main/java/fr/gouv/etalab/mastodon/activities/InstanceHealthActivity.java
@@ -192,7 +192,8 @@ public class InstanceHealthActivity extends BaseActivity {
                                 up.setTextColor(ContextCompat.getColor(getApplicationContext(), R.color.red));
                             }
                             uptime.setText(String.format("Uptime: %.2f %%", (instanceSocial.getUptime()*100)));
-                            checked_at.setText(String.format("Checked at: %s", Helper.dateToString(instanceSocial.getChecked_at())));
+                            if( instanceSocial.getChecked_at() != null)
+                                checked_at.setText(String.format("Checked at: %s", Helper.dateToString(instanceSocial.getChecked_at())));
                             values.setText(String.format("version: %s \n %s users - %s statuses", instanceSocial.getVersion(), withSuffix(instanceSocial.getUsers()), withSuffix(instanceSocial.getStatuses())));
                             instance_container.setVisibility(View.VISIBLE);
                             loader.setVisibility(View.GONE);
diff --git a/app/src/main/java/fr/gouv/etalab/mastodon/helper/Helper.java b/app/src/main/java/fr/gouv/etalab/mastodon/helper/Helper.java
index 3fc937f10..a6359cb72 100644
--- a/app/src/main/java/fr/gouv/etalab/mastodon/helper/Helper.java
+++ b/app/src/main/java/fr/gouv/etalab/mastodon/helper/Helper.java
@@ -498,6 +498,8 @@ public class Helper {
      * @return String
      */
     public static String dateToString(Date date) {
+        if( date == null)
+            return null;
         SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.getDefault());
         return dateFormat.format(date);
     }
diff --git a/app/src/main/java/fr/gouv/etalab/mastodon/jobs/NotificationsSyncJob.java b/app/src/main/java/fr/gouv/etalab/mastodon/jobs/NotificationsSyncJob.java
index 5361f946e..8b333e9db 100644
--- a/app/src/main/java/fr/gouv/etalab/mastodon/jobs/NotificationsSyncJob.java
+++ b/app/src/main/java/fr/gouv/etalab/mastodon/jobs/NotificationsSyncJob.java
@@ -80,22 +80,26 @@ public class NotificationsSyncJob extends Job {
     }
 
 
-    public static int schedule(boolean updateCurrent){
+    public static int schedule(boolean updateCurrent) {
 
         Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(NOTIFICATION_REFRESH);
         if (!jobRequests.isEmpty() && !updateCurrent) {
             return jobRequests.iterator().next().getJobId();
         }
 
-        return new JobRequest.Builder(NotificationsSyncJob.NOTIFICATION_REFRESH)
-                .setPeriodic(TimeUnit.MINUTES.toMillis(Helper.MINUTES_BETWEEN_NOTIFICATIONS_REFRESH), TimeUnit.MINUTES.toMillis(5))
-                .setUpdateCurrent(updateCurrent)
-                .setRequiredNetworkType(JobRequest.NetworkType.METERED)
-                .setRequirementsEnforced(false)
-                .build()
-                .schedule();
-    }
+        int jobRequestschedule = -1;
+        try {
+            jobRequestschedule = new JobRequest.Builder(NotificationsSyncJob.NOTIFICATION_REFRESH)
+                    .setPeriodic(TimeUnit.MINUTES.toMillis(Helper.MINUTES_BETWEEN_NOTIFICATIONS_REFRESH), TimeUnit.MINUTES.toMillis(5))
+                    .setUpdateCurrent(updateCurrent)
+                    .setRequiredNetworkType(JobRequest.NetworkType.METERED)
+                    .setRequirementsEnforced(false)
+                    .build()
+                    .schedule();
+        }catch (Exception ignored){}
 
+        return jobRequestschedule;
+    }
 
 
     /**