Matter.js light bulb pull

I want it to react when I pull the light bulb

What’s the problem?

I want an alarm to come when I pull the light bulb

but got a error

Uncaught TypeError: Cannot read properties of undefined (reading ‘position’)

    group = Body.nextGroup(true);

  var ropeB = Composites.stack(width/2, 100, 10, 1, 10, 10, function(x, y) {
    return Bodies.rectangle(x , y, 20, 4, {
      collisionFilter: { 
       group: group 
      }, 
      render : ropeRenderStyle
    });
  });

  const lamp =  Matter.Bodies.circle(width/2, 210, 30, {
      density: 0.0005,
                frictionAir: 0.06,
                restitution: 0.3,
                friction: 0.01,
                render: {
                    sprite: {
                        texture: './img/lamp.png',
                        xScale: 0.12,
                        yScale: 0.14
                    }
                }
    })

  Composite.add(ropeB, lamp);

  Composites.chain(ropeB, 0.5, 0, -0.5, 0, {
      stiffness: 0.8,
      length: 1,
      render: ropeRenderStyle
    });

  Composite.add(
      ropeB,
      Constraint.create({
        bodyB: ropeB.bodies[0],
        pointB: { x: 0, y: 0 },
        pointA: { x: ropeB.bodies[0].position.x, y: ropeB.bodies[0].position.y },
        stiffness: 0.5,
        render : ropeRenderStyle
      })
    );

    Events.on(engine, 'collisionStart', () => {
      const { bodies } = engine.world;
      const lamp = bodies.find(body => body.label === 'Circle Body');
      if (lamp.position.y < height) {
        alert("click");
      }   
    });