For the computer name, it can be with the domain join profile. Please check if the "Computer name prefix" under domain join profile is set as Desktop. We can see more details in the following link: https://learn.microsoft.com/en-us/mem/intune/configuration/domain-join-configure
Meanwhile, for the error, I find a similar issue which is related to OU permission. Please check if our permission is granted. https://www.risual.com/2021/04/autopilot-hybrid-domain-join-failure-80070002/ Note: Non-Microsoft link, just for the reference
However, if the error still exists, please check the event log running the connector to see if there's any more finding. Here is a troubleshooting article for the reference: https://oofhours.com/2020/07/19/troubleshooting-windows-autopilot-hybrid-azure-ad-join/ Note:Non-Microsoft link, just for the reference.