SPS Usermapping is not working

Hello,

I'm trying to authenticate SPS users through Active Directory and restrict users to use just root user on target server using usermapping.

But SSH connections can't start using this way of authentication.

kindly check my configuration steps:

1- Added LDAP server

2- User and access control > settings> Authentication settings > added LDAP

3- added usermapping 

4- added username on the server > root user on target server

5- added group > added domain group

6- added usermapping in SSH connection

7- enabled required gateway authentication >  added domain group in groups

your help is very appreciated