influxdb flux query for mqtt sensors

Question

I've some Shelly EM sensors flushing data into InfluxDb. I've this graph for the consumptions over time made by this query:

from(bucket: "shelly-em")
|> range(start: v.timeRangeStart, stop: v.timeRangeStop)

|> filter(fn: (r) =>
    r._measurement == "payload" and
    r._field == "numValue" and
    r.sensor == "power")
   
  |> aggregateWindow(every: 5m, fn: mean, createEmpty: false)
  |> map(fn: (r) => ({ r with _value: r._value  }))

The problem here is that I've the data divided also by the channel and device tag, and this query outputs 14 curves. I need to have one single curve that's the sum of all, I'm struggling but not being able to accomplish it..

Thanks