Bar graph problem: bars in dashboard are ok, then suddenly they become really thin

I have some graphs that uses bar plot mode and I’m grouping data by hour:

from(bucket: "dns-resolvers-bucket")
  |> range(start: v.timeRangeStart, stop:v.timeRangeStop)
  |> filter(fn: (r) =>
    r._measurement == "stats" and
    r._field =~ /num_(cachehits|cachemiss|prefetch|expired)/ and == "nas" and
    r.service == "unbound"
  |> derivative(
      unit: 1h,
      nonNegative: true,
      columns: ["_value"],
      timeColumn: "_time"
  |> aggregateWindow(every: 1h, fn: mean)

I’ve just opened the dashboard with a time-window of 24-hours and everything was fine, with good-looking bars with a reasonable width. I’ve started working on the dashboard, on other panels, and after some refreshes all the bars became really thin (same height/value, but much much thinner, almost a line). After a while they become slightly bigger.
The following image is the “slightly bigger” stage:

What could be the cause of this “problem”? Is there any way I can say "make the bar as large as 30 minutes, since I’m aggregating 1-hour periods of data?

Thank you in advance for any help

1 Like

As you can see now the same 24-hours graph shows prettier bars with a reasonable width.