Disconnect federation from a domain in Apple Business Manager
If you no longer plan to use federated authentication with a domain, you can disconnect the domain. This process does not affect the domain verification.
Note: You cannot disconnect from a federated domain if Apple Business Manager is in the process of enabling federation or the account transfer process has not been completed.
Disconnect federation from a domain
In Apple Business Manager
, sign in as a user that has the role of Administrator or People Manager.Select your name at the bottom of the sidebar, select Preferences
, then select Managed Apple Accounts 
.Select Manage next to the domain you want to remove federation from, then turn off “Sign in with [name of identity provider]”.
Select Confirm.