RDP application access policy directory account issue

Hello,

I have configured an RDP Application access policy > security > asset based session access > Directory Account 

but the login account in application can't take the full account format like: (abc@xyz.com), even it shown in the username connection string as (abc@xyz.com).

I have tried to use alternate login name with mapping to userPrincipalName  attribute, but issue still exists.

please advise how to edit it to pass the account details in right format.

thanks,