Remove device from groupe

I try to remove one of my device from the group, Ring camera battery, as it is the only camera with built-in light.
as long as it is in a group it is not possible to share the unit with others.
it has been shared before so the others can see it, but I can’t remove it from them nor add new users to see it.
someone that has a good tip how to handle this bug?
has chosen to remove it from the group and then saved, but it pops up there immediately after returning to the previous screen.