Dashboard RRD4J issues

Hello,
since some weeks I’m facing a issue with some dashboards. I’ve created some dashboards to get a historical view on my solar (Hot Water) production or for the solar electricity production as well. But on both, I have the same problem.
As you can see in the following splitted screen, the real time data are correct and updated. But the same values are not always correctly displayed on the dashboard (right panel).
In this exemple, we should have the solar sensor as well as the 2values for the hot water tank.

Instead , with have only the latest input and a direct straight line from the two/three days values.

My current setup is running a Openhab 5.0.2 within the Docker image.
The persistence of the data should be stored using RRD4J.

Would you have any guidance to help me?