How can I control Brightness and Color Temperature in Google Assistant?

currently I already have lamps integrated, but I only control their brightness, that’s no problem. But now I’m trying to integrate lamps where brightness and color temperature can be controlled.
I’ve already read through a few forum posts, but none could really help me.

First I created a group to which I assigned the items brightness and color temperature. In addition, the group has the GA metadata “light” and the items have the corresponding attributes.

In the current configuration, I can add the group to Google Home, but only the brightness is adjustable. The color temperature is assigned the same value as the brightness.

I’m probably just too stupid to read.

The Group:

My thanks to anyone willing to help

Because I’m a new user, I can only add one image per post.

The Color Temperature:

The Brightness: