public function execute(CommandInterface $command)
 {
     $registeredCustomer = $this->customerRegistrationFactory->make($command->getCustomerId(), $command->getFirstName(), $command->getLastNames(), $command->getUsername(), $command->getEmailAddress());
     $this->customerRepository->create($registeredCustomer);
 }
 public function execute(CommandInterface $command)
 {
     $customer = $this->customerRepository->find($command->getCustomerId());
     $customer->updateEmailAddress($command->getEmailAddress());
     $this->customerRepository->update($customer);
 }