Magento 2 getExtensionAttributes return null

I am writing an Observer to Magento\Customer\Account\Index but the Objects from class \Magento\Customer\Model\Customer return null when getExtensionAttributes is executed. $customer = $customerFactory->create()->load($customerID); //$customerRepository->get($customerID); $ext = $customer->getExtensionAttributes(); if($ext == null){ throw new \Exception(” var ext = null”); } I used CustomerRepository and CustomerFactory to get $customer