diff --git a/backend/internal/service/license.go b/backend/internal/service/license.go
index 51fe199..c479d70 100644
--- a/backend/internal/service/license.go
+++ b/backend/internal/service/license.go
@@ -21,7 +21,6 @@ var (
 	ErrLicenseNotFound   = errors.New("license not found")
 	ErrLicenseInactive   = errors.New("license is inactive")
 	ErrLicenseExpired    = errors.New("license has expired")
-	ErrDeviceMismatch    = errors.New("license is bound to another device")
 	ErrDeviceLimitExceed = errors.New("device limit reached — deactivate another device first")
 )
 
@@ -67,7 +66,9 @@ func (s *LicenseService) Activate(shopID uint64, licenseKey, deviceID, deviceNam
 	err := s.db.Where("license_id = ? AND device_id = ?", lic.ID, deviceID).First(&existing).Error
 	if err == nil {
 		// Device already bound — just touch last_seen_at (handled by autoUpdateTime)
-		s.db.Model(&existing).Update("device_name", deviceName)
+		if err := s.db.Model(&existing).Update("device_name", deviceName).Error; err != nil {
+			return nil, err
+		}
 		return &lic, nil
 	}
 
@@ -99,7 +100,7 @@ func (s *LicenseService) Verify(shopID uint64, deviceID string) (*model.License,
 		return nil, ErrLicenseNotFound
 	}
 	var lic model.License
-	if err := s.db.Where("id = ? AND is_active = 1", dev.LicenseID).First(&lic).Error; err != nil {
+	if err := s.db.Where("id = ? AND shop_id = ? AND is_active = 1", dev.LicenseID, shopID).First(&lic).Error; err != nil {
 		return nil, ErrLicenseNotFound
 	}
 	if lic.ExpiresAt != nil && time.Now().After(*lic.ExpiresAt) {