Mosquito MQTT missing sensor values

I implemented a sensor based on ESP32 with MQTT transfer to HA every 15 minutes.
This works beautifully, but if the sensor value is exactly the same as the last, I do not get an entry in the database and so grafana is unable to show a graph.
Is this intentionally? Can I change this behaviour and force HA (Mosquito ??) to save a sensor value whenever it is received and no matter if the value changed?

Thanks
Uli

Have a look at the force_update: option.