@alan G 

Thats the expected behavior of Ace. You can pair it directly without Sonos app via bluetooth to any device just to use it with its current configuration. 
But to do any settings on Ace you have to connect it to the Sonos mobile app. And that said… it means to every controller device separately. 
As Ace doesn’t work like a speaker and is not part of the multiroom system like a speaker, its config isn’t stored on every speaker and doesn’t show up automatically on every controller app. 

I also had some problems connecting Ace to an Android phone. But in the end it worked when Ace was paired to the phone but not connected. 

Thanks for that, I tried to establish that with customer support but failed to do so. It makes sense what you say , I have it connected now across multiple Android devices and showing in the app, except 1 my OnePlus nord. I just find it strange it connects to the phone but won't sync with the app with that one phone . 

@alan G

Sounds strange… Android isn’t my daily business as I‘m a Apple user, but on my Android test phone I gave Sonos app some permissions like „looking for other network devices“ ans „location servicees“. Do you have activated all of them available for Sonos app?

Just ran a check there and they are all activated on the app. I think I'll try another non Samsung android to isolate it's a phone / app issue.. if that is possible but would seen strange seen as though the Bluetooth connection works fine.