Identity Governance automatically closes an SoD case on any of the following conditions:
It detects that enough permissions and roles have been removed from the user or account that is in violation so that the SoD violation is no longer detected.
Someone deletes the SoD policy. All SoD violations for the SoD policy cease to exist when the policy does not exist.
Someone changes the conditions of the SoD policy such that the SoD violation no longer exists.
The violating user or account is no longer found in the catalog.