Google Home app reportStateResponse Error

I am using a group with 20 dimmers. When I send on or off to the group, I get a numer of errors from the Google Home app. Why is this? Does it matter? How do I get rid of it? Google Home integrations seems to work reasonably well otherwise (see below)

app:34 2022-03-13 22:26:16.804 error reportStateResponse Error: {
  "error": {
    "code": 400,
    "message": "Request contains an invalid argument.",
    "status": "INVALID_ARGUMENT"
  }
}

Related or not? When I say "Hello Google, tänd arbetsrummet" (turn on the lights in my study), both lamps in the room turns on, although the log only shows one of them (together with the error message as above). The same results for other rooms with two lamps. Here is a sample from the log:

app:342022-03-13 22:36:09.259 errorreportStateResponse Error: {
  "error": {
    "code": 400,
    "message": "Request contains an invalid argument.",
    "status": "INVALID_ARGUMENT"
  }
}
app:342022-03-13 22:36:07.209 errorreportStateResponse Error: {
  "error": {
    "code": 400,
    "message": "Request contains an invalid argument.",
    "status": "INVALID_ARGUMENT"
  }
}
dev:2342022-03-13 22:36:06.964 infoZ05 Arbetsrummet - Taklampa is 99% [digital]
dev:2342022-03-13 22:36:06.960 infoZ05 Arbetsrummet - Taklampa was turned on [digital]