If you are seeing “Ownerless group policy configuration failed” and “Please try again.” error message:

there might be some different reasons:

1. Microsoft said it is (was) a know problem – it happens sometimes (timeout?), if you configured the policy properly and have enough permissions.
   So just go back one step and try again – all should be good.
   
2. Sometimes “Ownerless group policy configuration failed. Failure in configuring ownerless groups policy” is a permissions issue
   SharePoint admin, Teams admin: cannot configure Ownerless Groups Policy
   Global admin: yes, can configure Ownerless Microsoft 365 Groups Policy.
   What is the minimum role required?
   According to a recent update of the Microsoft’s article – “A Global administrator can create a policy…”. In my experience – groups admin can also configure the policy

Note: Groups admin when configuring the policy can see warning message “You don’t have permissions to save changes”.
No worries 🙂 => You will be able to save changes 🙂

Video tutorial on the policy configuration (at around 5:00 you can see this error message):