Google Assistant, 1 entity (voulme) is not working for another user

Configuration
1

hello,

using nabu casa edition, i have exposed lots of lights/switches to GA, everyting working as it should

i have also exposed my media player, like in config below
this is the only entity thats NOT working for other persons that are speaking to the google home mini , only works when i say it

so for instance =
set volume on 25 => media player goes to level 25
if my wife or other persons saying that exact same thing => got a response, like there is no linked service bla bla …

checked that phrase with the myactivity.google.com site, so it was correct for the other person

relinking or synching doesnt make any difference

    media_player.denon_avrx4000:
      name: Volume
      room: Harmony

media_player.denon_avrx4000:
  device_class: speaker
2

what i also notice on myactivity , see screenshot below, that for the volume commands , i dont see the link to homeautomation … like the lights/switches , but the command is actually triggered fine in HA