Grafana error with query

Hello,

I’ve an influx database for persisting values. This seems to work as i’m able to query the db (see blue). But when I want to visualize these values in grafana, I get an error for my query, i’m getting an Influx db error : GROUP BY requires at least on aggregate function.
Why is that, what am i doing wrong ? How can I visualize the data ?

Tkx
Best wishes
Leo

OK, solved, found the solution.
Tkx
Leo