diff --git a/resources/js/components/TimeTrackers/Tracker.tsx b/resources/js/components/TimeTrackers/Tracker.tsx
index ad1002b..f4183fe 100644
--- a/resources/js/components/TimeTrackers/Tracker.tsx
+++ b/resources/js/components/TimeTrackers/Tracker.tsx
@@ -31,8 +31,8 @@ const Tracker = () => {
     return <div>
         {currentTimeTracker
             ? <div className="flex gap-2">
-                <Link to={`/todos/${currentTimeTracker.to_do.id}`} className="font-bold">
-                    {currentTimeTracker.to_do.name}
+                <Link to={`/todos/${currentTimeTracker?.to_do.id}`} className="font-bold">
+                    {currentTimeTracker?.to_do.name}
                 </Link>
                 <span>{timer}</span>
                 <button onClick={stopCurrentTimeTrack} className="flex items-center">
diff --git a/resources/js/pages/TimeTrackersIndex.tsx b/resources/js/pages/TimeTrackersIndex.tsx
index 0b31dd6..93c62d8 100644
--- a/resources/js/pages/TimeTrackersIndex.tsx
+++ b/resources/js/pages/TimeTrackersIndex.tsx
@@ -36,7 +36,7 @@ const TimeTrackersIndex = () => {
                 <span className="text-center w-36">{(new Date(tracker.end_at)).toSmallFrDate()}</span>
                 <span className={`flex-1 ${tracker.to_do.checked ? 'line-through' : ''}`}>{tracker.to_do.name}</span>
                 <span className="flex gap-2">
-                    {!tracker.to_do.checked && <button className="cursor-pointer  w-7 justify-center flex items-center"
+                    {!tracker?.to_do.checked && <button className="cursor-pointer  w-7 justify-center flex items-center"
                             type="button"
                             title="Commencer"
                             onClick={() => startTrackToDo(tracker.to_do)}>