What is the make/model of the TV it’s connected to?

LG TV and she has Dolby atmos
When the Sonos is not connected to the TV I have the indication Dolby vision and Dolby atmos

These are the usual settings that are used for for LG TV’s…

Sound -> HDMI ARC (Digital Sound Out = Pass-Through / eARC = ‘ON’)

Sound -> Additional Settings (DTV Audio = Auto) / HDMI input format = Bitstream for all HDMI ports.

Connection -> HDMI Device Settings (Auto Device Detection = ‘ON’ / Simplink = ‘ON’ / Auto Power Sync = ‘ON’)

Also what A/V source device/App are you using for the output?

Thank’s I’m gonna check the settings tomorrow 

I use a AppleTV 4K and for that I don’t know if it’s better to connect the Sonos directly on the AppleTV with audio optic or on tv with hdmi eARC?

The  Beam should be connected to HDMi-2 (eARC port) and the Apple TV can be connected to any one of your other HDMI ports - the Apple TV does not need an audio return channel - It’s audio output (LPCM - Dolby MAT) ‘by default’ will simply output via/through the TV over the HDMI connection, but it needs eARC to be enabled on the TV sound out, as the audio is uncompressed.

Thank you for your help 

i just changed the settings of tv and it’s working