User Name with double Prefix shown in Manager Web UI

Hey Guys,
it´s just a beauty problem, but when we log in to RHV-M via AD authentication the logged in user is shown like: "username@domain.com@domain.com".
Does anyone know how to change this to username@domain.com.
I think the problem is that RHV-M is getting the UserPrincipalName from AD and maps this to UserPrincipalName@domain.com. But how can I change this without changing the principal name?

Thanks