Nested AD groups does not show the uppermost parent

[thgmx]

Hello

I  configured a user directory "MY_USERS" in Confluence Adminsitration -> User Directories. MY_USERS is a (nested) Microsoft Active Directory. This AD contains a lot of other nested ADs and some persons. 

Everything works fine except when I try to set MY_USERS as global permission: Edit Permissions -> input MY_USERS -> No matches found.

In Confluence aministration -> Groups there are all groups listed which are contained in MY_USERS but not MY_USERS itself.

I found nothing which could help me in Connecting to an LDAP Directory .

Can anybody help?

Thanks in advance

Best regards

By the way: I work with Confluence 6.13.4 on Windows10.