AC-14241::Not able to place the order with the guest

Author: glo60612

app/code/Magento/Quote/Model/CustomerManagement.php

@@ -163,6 +163,7 @@ public function validateAddresses(QuoteEntity $quote)
             $billingAddress = $quote->getBillingAddress();
             $customerAddress = $this->customerAddressFactory->create();
             $customerAddress->setFirstname($billingAddress->getFirstname());
+            $customerAddress->setMiddlename($billingAddress?->getMiddlename());
             $customerAddress->setLastname($billingAddress->getLastname());
             $customerAddress->setStreet($billingAddress->getStreet());
             $customerAddress->setCity($billingAddress->getCity());