Can't delete 3 different member servers in AD Audit Plus

Can't delete 3 different member servers in AD Audit Plus

Actually I can delete them, but after a while (hours) they are automatically in the list again.
I have tried to delete them 3 times now.
When they are in the list, they fails to fetch event log data, because they are deleted from the AD and does not exist anymore.
How can they be removed from permanently from AD Audit Plus?