I’m guessing you have them set up as two disparate systems, although I’m unsure because it isn’t clear what you have to do to ‘see’ the other one.
If my assumption is correct, you need to factory reset just one of those devices, and only that one. Then connect to the other one, and use the ‘add a device’ function in the controller. Once it has been re-added, both should show up in your controller, and you can group them
Hi @Kenoooooo
Welcome to the Sonos Community!
I just looked for you and confirmed - @Airgetlam is correct.