diff --git a/app/carnet/page.tsx b/app/carnet/page.tsx
index 845c1da9..b5c97f2a 100644
--- a/app/carnet/page.tsx
+++ b/app/carnet/page.tsx
@@ -169,15 +169,25 @@ export default function CarnetPage() {
         const vcard = new VCard();
         vcard.parse('BEGIN:VCARD' + section);
         
+        // Extract contact properties with proper type handling
+        const uid = vcard.getProperty('UID')?.value;
+        const fullName = vcard.getProperty('FN')?.value;
+        const email = vcard.getProperty('EMAIL')?.value;
+        const phone = vcard.getProperty('TEL')?.value;
+        const organization = vcard.getProperty('ORG')?.value;
+        const address = vcard.getProperty('ADR')?.value;
+        const notes = vcard.getProperty('NOTE')?.value;
+        const group = vcard.getProperty('CATEGORIES')?.value;
+        
         return {
-          id: vcard.getProperty('UID')?.value || Math.random().toString(36).substr(2, 9),
-          fullName: vcard.getProperty('FN')?.value || '',
-          email: vcard.getProperty('EMAIL')?.value || '',
-          phone: vcard.getProperty('TEL')?.value || '',
-          organization: vcard.getProperty('ORG')?.value || '',
-          address: vcard.getProperty('ADR')?.value || '',
-          notes: vcard.getProperty('NOTE')?.value || '',
-          group: vcard.getProperty('CATEGORIES')?.value || ''
+          id: uid || Math.random().toString(36).substr(2, 9),
+          fullName: fullName || 'Unknown Contact',
+          email: email || '',
+          phone: phone || '',
+          organization: organization || '',
+          address: address || '',
+          notes: notes || '',
+          group: group || ''
         };
       });
     } catch (error) {
@@ -479,8 +489,11 @@ export default function CarnetPage() {
   const generateVCard = (contact: Contact): string => {
     const vcard = new VCard();
     
-    vcard.setProperty('UID', contact.id);
-    vcard.setProperty('FN', contact.fullName);
+    // Ensure required fields are not undefined
+    vcard.setProperty('UID', contact.id || Math.random().toString(36).substr(2, 9));
+    vcard.setProperty('FN', contact.fullName || 'Unknown Contact');
+    
+    // Add optional fields only if they have values
     if (contact.email) vcard.setProperty('EMAIL', contact.email);
     if (contact.phone) vcard.setProperty('TEL', contact.phone);
     if (contact.organization) vcard.setProperty('ORG', contact.organization);