Why did the creation of an alternative account owner trusted profile fail?

A trusted profile is created without the classic infrastructure permissions that an alternative account owner is normally assigned. You receive an error after you create the trusted profile.

An error occured while trying to apply the admin flag for this account. An error occurred. Try again later. Only 1 TrustedProfile per account may be set as the alternate master user.

You might already have an alternative account owner trusted profile in the account. You can set only one trusted profile as the alternative account owner.

Delete the trusted profile that has an error. Check the account for an existing trusted profile with alternative account owner access, which is indicated by an alt account owner tag. If no such profile exists, try creating the trusted profile again.

For more information, see Setting an alternative account owner.