diff --git a/app/api/storage/files/route.ts b/app/api/storage/files/route.ts
index 17467c2..7a0f8b4 100644
--- a/app/api/storage/files/route.ts
+++ b/app/api/storage/files/route.ts
@@ -252,31 +252,50 @@ export async function PUT(request: Request) {
     // Check if this is using the direct id (key) or needs to construct one
     let key: string;
     
-    // For Diary and Health folders, always reconstruct key from title to ensure new format
-    // This allows renaming from "2026-01-16.md" to "16_janvier_2026.md"
     const normalizedFolder = folder?.toLowerCase() || '';
     const isDiaryOrHealth = normalizedFolder === 'diary' || normalizedFolder === 'health';
     
-    if (id && !isDiaryOrHealth) {
-      // For non-Diary/Health folders, use the provided id if available
-      // Ensure the user can only access their own files
-      if (!id.includes(`user-${userId}/`)) {
+    // For Diary/Health, if id is provided and it's in the correct format, use it
+    // Otherwise, reconstruct from title (for migration from old format)
+    if (id && id.includes(`user-${userId}/`)) {
+      // Validate that the id is for the correct folder
+      if (id.includes(`/${normalizedFolder}/`)) {
+        // For Diary/Health, verify the id matches the expected format
+        if (isDiaryOrHealth) {
+          // Check if the id already matches the sanitized title format
+          const sanitizedTitle = title ? title.replace(/[^a-zA-Z0-9._-]/g, '_') : '';
+          const expectedKey = `user-${userId}/${normalizedFolder}/${sanitizedTitle}${sanitizedTitle.endsWith('.md') ? '' : '.md'}`;
+          
+          // If id matches expected format, use it (this is an update to existing file)
+          if (id === expectedKey) {
+            key = id;
+            console.log(`[PUT] Using provided id for Diary/Health: ${key}`);
+          } else {
+            // Id doesn't match expected format, but it's a valid id for this folder
+            // Use it anyway (this handles updates to existing files with old format)
+            key = id;
+            console.log(`[PUT] Using provided id for Diary/Health (format mismatch, but valid): ${key}`);
+          }
+        } else {
+          // For non-Diary/Health folders, use the provided id
+          key = id;
+        }
+      } else {
         return createErrorResponse(
           StorageError.FORBIDDEN,
-          'Unauthorized access to file',
+          'File id does not match the specified folder',
           403,
-          { fileId: id }
+          { fileId: id, folder: normalizedFolder }
         );
       }
-      key = id;
     } else {
-      // If id is not provided, or for Diary/Health folders, construct it from folder and title
+      // If id is not provided or invalid, construct it from folder and title
       if (!title || !folder) {
         return createErrorResponse(
           StorageError.VALIDATION_ERROR,
           'Missing required fields: either id or (title and folder) must be provided',
           400,
-          { received: { title: !!title, folder: !!folder } }
+          { received: { title: !!title, folder: !!folder, id: !!id } }
         );
       }
 
@@ -295,13 +314,7 @@ export async function PUT(request: Request) {
       const sanitizedTitle = title.replace(/[^a-zA-Z0-9._-]/g, '_');
       key = `user-${userId}/${normalizedFolder}/${sanitizedTitle}${sanitizedTitle.endsWith('.md') ? '' : '.md'}`;
       
-      // If this is Diary/Health and we have an old id, we might need to delete the old file
-      // But for now, we'll just create/update with the new key
-      if (isDiaryOrHealth && id && id !== key) {
-        console.log(`[PUT] Renaming Diary/Health note from ${id} to ${key}`);
-        // The old file will remain, but the new one will be created/updated
-        // In a future enhancement, we could delete the old file here
-      }
+      console.log(`[PUT] Constructed key from title for ${normalizedFolder}: ${key}`);
     }
 
     // Validate content
diff --git a/app/pages/page.tsx b/app/pages/page.tsx
index 5234304..a96bca4 100644
--- a/app/pages/page.tsx
+++ b/app/pages/page.tsx
@@ -509,29 +509,40 @@ export default function CarnetPage() {
         
         // ALWAYS check if a note with this date already exists (even if note.id is set)
         // This ensures we update the existing note instead of creating a duplicate
+        console.log(`[handleSaveNote] Checking for existing note. Date: ${dateTitle}, DateStr: ${dateStr}, Notes count: ${notes.length}`);
+        console.log(`[handleSaveNote] Current notes:`, notes.map(n => ({ title: n.title, id: n.id })));
+        
         const existingNote = notes.find(n => {
           const title = n.title || '';
           const noteId = n.id || '';
           // Check multiple patterns to find the existing note
-          return title === dateTitle || 
+          const matches = title === dateTitle || 
                  title === dateStr ||
                  title.startsWith(dateStr) || 
                  title.startsWith(dateTitle) ||
                  noteId.includes(dateStr) ||
-                 noteId.includes(dateTitle.replace(/\s/g, '_'));
+                 noteId.includes(dateTitle.replace(/\s/g, '_')) ||
+                 noteId.includes(dateTitle.replace(/\s/g, '-'));
+          
+          if (matches) {
+            console.log(`[handleSaveNote] Found matching note:`, { title, id: noteId });
+          }
+          return matches;
         });
         
         if (existingNote) {
           // Update the existing note instead of creating a new one
-          console.log(`[handleSaveNote] Found existing note for today, updating: ${existingNote.id}`);
+          console.log(`[handleSaveNote] Found existing note for today, updating: ${existingNote.id}, title: ${existingNote.title}`);
           note.id = existingNote.id;
           noteTitle = existingNote.title || dateTitle; // Keep the existing title format
-          // Use the existing note's id as the fileKey
+          // Use the existing note's id as the fileKey - this is critical!
           fileKey = existingNote.id;
+          console.log(`[handleSaveNote] Using existing fileKey: ${fileKey}`);
         } else {
           // No existing note found, create new one with formatted date title
           // The fileKey will be constructed from the formatted title
           fileKey = `user-${session?.user?.id}/${selectedFolder.toLowerCase()}/${dateTitle}${dateTitle.endsWith('.md') ? '' : '.md'}`;
+          console.log(`[handleSaveNote] No existing note found, creating new with fileKey: ${fileKey}`);
         }
       } else {
         // For other folders, use existing id or construct from title