diff --git a/components/calendar/calendar-client.tsx b/components/calendar/calendar-client.tsx
index 820d3a40..d4ccd3c1 100644
--- a/components/calendar/calendar-client.tsx
+++ b/components/calendar/calendar-client.tsx
@@ -1074,10 +1074,12 @@ export function CalendarClient({ initialCalendars, userId, userProfile }: Calend
                         <div className="flex items-center gap-1.5 text-xs text-white">
                           {!arg.event.allDay && (
                             <span className="font-medium whitespace-nowrap shrink-0">
-                              {arg.event.start && new Date(arg.event.start).toLocaleTimeString('fr-FR', {
-                                hour: '2-digit',
-                                minute: '2-digit'
-                              })}
+                              {typeof arg.event.start === 'object' && arg.event.start instanceof Date 
+                                ? arg.event.start.toLocaleTimeString('fr-FR', {
+                                    hour: '2-digit',
+                                    minute: '2-digit'
+                                  })
+                                : ''}
                             </span>
                           )}
                           <span className="font-medium truncate max-w-[calc(100%-4.5rem)]">
@@ -1091,10 +1093,12 @@ export function CalendarClient({ initialCalendars, userId, userProfile }: Calend
                         <p className="font-medium">{arg.event.title}</p>
                         {!arg.event.allDay && (
                           <p className="text-xs text-gray-400 mt-1">
-                            {arg.event.start && new Date(arg.event.start).toLocaleTimeString('fr-FR', {
-                              hour: '2-digit',
-                              minute: '2-digit'
-                            })}
+                            {typeof arg.event.start === 'object' && arg.event.start instanceof Date 
+                              ? arg.event.start.toLocaleTimeString('fr-FR', {
+                                  hour: '2-digit',
+                                  minute: '2-digit'
+                                })
+                              : ''}
                           </p>
                         )}
                       </div>