diff --git a/src/services/crm-email.service.js b/src/services/crm-email.service.js
index b6a7668..e73d80d 100644
--- a/src/services/crm-email.service.js
+++ b/src/services/crm-email.service.js
@@ -209,11 +209,40 @@ export const markContactEmailsAsRead = async (userId, contactId) => {
     });
   }
 
-  const result = await db
-    .update(emails)
-    .set({ isRead: true, updatedAt: new Date() })
-    .where(and(eq(emails.userId, userId), eq(emails.contactId, contactId), eq(emails.isRead, false)))
-    .returning();
+  // FIX: Mark emails as read by matching sender EMAIL, not just contactId
+  // This fixes the issue with duplicate contacts having different IDs
+  let result = [];
+
+  if (contact) {
+    // Update ALL emails from this sender's email address:
+    // 1. Set the correct contactId (fixes duplicate contact issue)
+    // 2. Mark as read
+    result = await db
+      .update(emails)
+      .set({
+        contactId: contactId,  // Fix contactId for duplicate contacts
+        isRead: true,
+        updatedAt: new Date()
+      })
+      .where(and(
+        eq(emails.userId, userId),
+        or(
+          eq(emails.from, contact.email),
+          like(emails.from, `%<${contact.email}>%`)
+        ),
+        eq(emails.isRead, false)
+      ))
+      .returning();
+
+    console.log('🔧 Fixed contactId and marked as read for emails from:', contact.email);
+  } else {
+    // Fallback: use old method if contact not found
+    result = await db
+      .update(emails)
+      .set({ isRead: true, updatedAt: new Date() })
+      .where(and(eq(emails.userId, userId), eq(emails.contactId, contactId), eq(emails.isRead, false)))
+      .returning();
+  }
 
   console.log('✅ markContactEmailsAsRead result:', { count: result.length, contactId });