Work phone availability while on break?

Sooo….I was told yesterday that the expectation from leadership is that nurses carry their work phone at all times: including during lunch and any breaks. If this is the expectation, it doesn’t seem like a “break”. Shouldn’t they have to pay you for your lunch break since the expectation is that you are available? The logic I was told is that the charge nurse can’t be expected to know about all the patients on the floor while nurses are on lunch/breaks. For context, I am in AR and work 12 hour shifts. Thoughts?!!? Is this common at other facilities?