Extract Daily Values

Hi Community

I think I have a similar problem.
i use grafana with influxdb and I’m collecting values from OpenHab.
Database in very simple, 2 columns:

time
value

Openhab save valuee for power consumption in €.
I get the representation of daily consumption in grafana not shown exactly.

Example Date: 06.06.2017

I have export the database from influx and have counted the values from 06.06.2017.
The result was 0,125€.

In grafana i have group by time (1d) and select difference and test some aggregations (distinct, mean, median and mode)
but nothing show me the right value.
I’m not sure what I have to adjust.
And why is the time off a bar from a single day every 02:00:00?

I need some help please