diff --git a/app/agenda/page.tsx b/app/agenda/page.tsx
index 4f757c8..7a2dbd5 100644
--- a/app/agenda/page.tsx
+++ b/app/agenda/page.tsx
@@ -181,7 +181,7 @@ export default async function CalendarPage() {
     for (const account of infomaniakAccounts) {
     // Check if a calendar sync already exists for this account (enabled or disabled)
     // This prevents creating duplicate calendars for the same account
-    const existingSync = await prisma.calendarSync.findFirst({
+    let existingSync = await prisma.calendarSync.findFirst({
       where: {
         mailCredentialId: account.id
       },
@@ -189,6 +189,48 @@ export default async function CalendarPage() {
         calendar: true
       }
     });
+    
+    // If no sync found by mailCredentialId, check if there's an orphaned sync with same email
+    // This handles the case where user deleted and re-added the account (new mailCredentialId, same email)
+    if (!existingSync) {
+      const orphanedSyncByEmail = await prisma.calendarSync.findFirst({
+        where: {
+          provider: 'infomaniak',
+          calendar: {
+            userId: session?.user?.id || '',
+            name: 'Privée'
+          },
+          mailCredential: {
+            email: account.email
+          }
+        },
+        include: {
+          calendar: true,
+          mailCredential: true
+        }
+      });
+      
+      if (orphanedSyncByEmail && orphanedSyncByEmail.mailCredential?.email === account.email) {
+        console.log(`[AGENDA] Found orphaned Infomaniak sync for email ${account.email}, reassigning to new mailCredentialId ${account.id}`);
+        // Reassign the sync to the new mailCredentialId
+        await prisma.calendarSync.update({
+          where: { id: orphanedSyncByEmail.id },
+          data: {
+            mailCredentialId: account.id,
+            syncEnabled: true
+          }
+        });
+        // Reload the sync
+        existingSync = await prisma.calendarSync.findFirst({
+          where: {
+            mailCredentialId: account.id
+          },
+          include: {
+            calendar: true
+          }
+        });
+      }
+    }
 
     // If sync exists but is disabled, check if it's due to invalid credentials
     // Don't re-enable if the last error was 401 (invalid credentials)
@@ -567,6 +609,7 @@ export default async function CalendarPage() {
   // No default calendar creation - only synced calendars from courrier
   
   // Debug: Verify Infomaniak calendars exist in database
+  // Check both by provider and by mailCredential email
   const allInfomaniakSyncs = await prisma.calendarSync.findMany({
     where: {
       provider: 'infomaniak',
@@ -579,9 +622,30 @@ export default async function CalendarPage() {
       mailCredential: true
     }
   });
-  console.log(`[AGENDA] Found ${allInfomaniakSyncs.length} Infomaniak syncs in database`);
-  allInfomaniakSyncs.forEach(sync => {
-    console.log(`[AGENDA] Infomaniak sync: id=${sync.id}, calendarId=${sync.calendarId}, calendarName=${sync.calendar?.name}, syncEnabled=${sync.syncEnabled}, mailCredentialId=${sync.mailCredentialId}, hasMailCredential=${!!sync.mailCredential}`);
+  
+  // Also check for syncs linked to Infomaniak accounts by email (in case mailCredentialId changed)
+  const infomaniakEmails = infomaniakAccounts.map(acc => acc.email);
+  const syncsByEmail = await prisma.calendarSync.findMany({
+    where: {
+      provider: 'infomaniak',
+      calendar: {
+        userId: session?.user?.id || ''
+      },
+      mailCredential: {
+        email: {
+          in: infomaniakEmails
+        }
+      }
+    },
+    include: {
+      calendar: true,
+      mailCredential: true
+    }
+  });
+  
+  console.log(`[AGENDA] Found ${allInfomaniakSyncs.length} Infomaniak syncs by provider, ${syncsByEmail.length} by email`);
+  [...allInfomaniakSyncs, ...syncsByEmail].forEach(sync => {
+    console.log(`[AGENDA] Infomaniak sync: id=${sync.id}, calendarId=${sync.calendarId}, calendarName=${sync.calendar?.name}, syncEnabled=${sync.syncEnabled}, mailCredentialId=${sync.mailCredentialId}, email=${sync.mailCredential?.email || 'none'}, hasMailCredential=${!!sync.mailCredential}`);
   });
   
   // Debug: Log calendars before filtering