I am sorry, but Sara cannot determine your SendAs permission issue. Delegate {1} does have proper permissions for Principal ...

I am sorry, but Sara cannot determine your SendAs permission issue. Delegate {1} does have proper permissions for Principal {0}. Please note that recent changes in delegate permissions can take up to two hours to be reflected. If it has been longer, please try removing all delegate permissions via the principal mailbox and recreate the permission. Otherwise, please file a support ticket with your administrator and someone will be able to help you personally with your issue.