Zigbee Thermostat radiator valve - How?

Hello, i added to my zigbee network a
BSEED SMART THERMOSTAT / BSEED TV-02 ZG
with Zigbee2MQTT

and with Simple-Thermostat on my Dashboard

So, i want to control the temperature with a Schedule.

but it work not correct. the target temperture should be 20° (schedule), not 21° (dashboard).

what is wrong here?

thx in advance for help