Holds Resolution process failing due to Validate Payables Invoice scheduled process

Summary:

Since 25D upgrade, Holds Resolution processes for Invoices are failing due to 'Validate Payables Invoice' scheduled process.

Content (please ensure you mask any confidential information):

If validating an invoice manually, the Holds Resolution process works fine, but if validated using the 'Validate Payables Invoice' scheduled process, it fails with error: MOAC Priv Name cannot be null; Initialize MOAC. Error due to health of managed servers.

SR has been raised, but technician thinks it's a bug with Invoice approval process, which is not the case. It should be sending a Holds Resolution notification to PO Owner to receipt against PO, so Invoice remains on Needs Revalidation. Not even getting to Invoice approval stage.