Setting a parent account while creating a new account in CRM

Hi,

I am trying to create a new account in CRM Sandbox by using SDK, and in the process would like to set a parent account as well:

But what happens at the end of account creation -- I get the following:

An empty string or empty array?

What I did:

a. I fetched the parent account:

$accountParent = Record::getRecordUsingExternalId($this->customerId, 'Accounts')->getObject()->getData()[0]; // returns the expected class com\zoho\crm\api\record\Record

b. I set the accounts attribute ParentAccount and created a record

$record1->addFieldValue(Accounts::AccountName(), $accountName); // test12
$record1->addFieldValue(Accounts::ParentAccount(), $accountParent); // an object with keyValues[] and keyModified[]
return $recordOperations->createRecords($moduleAPIName, $bodyWrapper);

c. The result is an empty array of the Parent Account, and very often the empty Account Name (like [], because of 500 - internal server error on Zoho?) https://drive.google.com/file/d/1Ep391dqbIvm0IVGtIBBcLEX3fO0EyDWw/view?usp=sharing

d. I digged a little bit in your code and

$convertInstance = $this->getConverterClassInstance(strtolower($this->contentType));
$requestObject = $convertInstance->formRequest($this->request, get_class($this->request), null, null);

Line 1 has the right data, but line 2 has an empty array for Account Parent

Can you please help me out here? Did I do eveything right?

Best regards