Why do I get no data from the same influx query in alert rule as in the dashboard?

Question

I create a Grafana Visu with the following influx query:

import "math"
from(bucket: "IoT")
  |> range(start: v.timeRangeStart, stop: v.timeRangeStop)
  |> filter(fn: (r) => r["host"] == "0a1d52e4da06")
  |> sort(columns: ["_time"], desc: true)
  |> elapsed(unit: 1s)
  |> filter(fn: (r) => r["_value"] == false)
  |> keep(columns: ["elapsed", "_time"])

Now, I want to create an alert rule and starts with the same query, but I get no data:

Why do I get data for the time-series graph, but not for the alert rule?