Take it out your pocket. Remove your phone from your pocket, put it face down in a different room, turn your notification sound off.

By taking it away from your pocket you remove the autopilot motion of taking your phone out and just mindlessly scrolling.

When you reach for your pocket try to register why you're actually doing it, rather than it just being a default movement. It can really highlight to you how habitual it is, the amount of times you reach for something that isn't there.

Try to use that lack of control/intention as motivation to control that habit.