diff --git a/scripts/diagnose-register.sh b/scripts/diagnose-register.sh
new file mode 100755
index 000000000..349ab0b97
--- /dev/null
+++ b/scripts/diagnose-register.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+
+# Script de diagnostic pour le problème de register
+
+TIMESTAMP=$(date +%s)
+TEST_EMAIL="diagnose-${TIMESTAMP}@example.com"
+TEST_USERNAME="user${TIMESTAMP}"
+TEST_PASSWORD="MySecurePass2024!@#"
+
+echo "=== DIAGNOSTIC REGISTER ==="
+echo ""
+echo "1. Testing register endpoint..."
+REGISTER_RESPONSE=$(curl -s -X POST "http://localhost:8080/api/v1/auth/register" \
+  -H "Content-Type: application/json" \
+  -d "{\"email\":\"$TEST_EMAIL\",\"username\":\"$TEST_USERNAME\",\"password\":\"$TEST_PASSWORD\",\"password_confirm\":\"$TEST_PASSWORD\"}")
+
+echo "$REGISTER_RESPONSE" | jq .
+
+echo ""
+echo "2. Checking HTTP status code..."
+HTTP_CODE=$(curl -s -o /dev/null -w "%{http_code}" -X POST "http://localhost:8080/api/v1/auth/register" \
+  -H "Content-Type: application/json" \
+  -d "{\"email\":\"$TEST_EMAIL\",\"username\":\"$TEST_USERNAME\",\"password\":\"$TEST_PASSWORD\",\"password_confirm\":\"$TEST_PASSWORD\"}")
+echo "HTTP Code: $HTTP_CODE"
+
+echo ""
+echo "3. Testing with different password (no common words)..."
+TEST_PASSWORD2="XyZ987AbC!@#"
+REGISTER_RESPONSE2=$(curl -s -X POST "http://localhost:8080/api/v1/auth/register" \
+  -H "Content-Type: application/json" \
+  -d "{\"email\":\"diagnose2-${TIMESTAMP}@example.com\",\"username\":\"user2${TIMESTAMP}\",\"password\":\"$TEST_PASSWORD2\",\"password_confirm\":\"$TEST_PASSWORD2\"}")
+echo "$REGISTER_RESPONSE2" | jq .
+
+echo ""
+echo "=== RECOMMENDATIONS ==="
+echo "1. Vérifier que le backend a été redémarré avec le nouveau code"
+echo "2. Vérifier les logs du backend pour voir l'erreur exacte"
+echo "3. Vérifier la connexion à la base de données"
+echo "4. Vérifier que les migrations ont été exécutées"
+
diff --git a/veza-backend-api/internal/core/auth/service.go b/veza-backend-api/internal/core/auth/service.go
index c3d90934e..ec6be6d32 100644
--- a/veza-backend-api/internal/core/auth/service.go
+++ b/veza-backend-api/internal/core/auth/service.go
@@ -143,6 +143,7 @@ func (s *AuthService) Register(ctx context.Context, email, username, password st
 		Role:         "user",     // Valeur par défaut
 		IsActive:     true,       // Valeur par défaut
 		IsVerified:   false,     // Valeur par défaut
+		TokenVersion: 0,         // Valeur par défaut (required NOT NULL field)
 	}
 
 	if err := s.db.WithContext(ctx).Create(user).Error; err != nil {