Change set temperatur via KNX

Hello everybody,

I have an openhab2 installation running on a Raspberry pI 3.
The interface to the KNX is an MDT IP interface, which works very well.
So far I have been able to control blinds, lamps and sockets with it.
Now I would like to be able to set the target temperature for each room.
The previous temperature control takes place via MDT glass pushbuttons by means of a setpoint shift (2 bytes).
For this purpose, I created the channels for actual temperature, setpoint temperature and setpoint shift in openhab.
It is possible to change the setpoint temperature or the setpoint shift in an overview.
However, the change in the setpoint temperature is not displayed on the MDT glass buttons.

Does anyone have any ideas where I might have to adjust something?

thank you very much