Arcade group messes with my sprite's physics

Phaser 3
1

I got this

class Thing extends Phaser.Physics.Arcade.Sprite
{

  constructor(scene, x, y)
  {
    super(scene, x, y, "lol")
    scene.add.existing(this)
    scene.physics.add.existing(this, false)
    this.setDragX(0.001)
    this.setDragY(0.001)
    this.setDamping(true)

  }

}

When I add them to a group, then the damping is ignored:

this.group = this.physics.add.group()
this.a = new Being(this, 50, 50)
this.b = new Being(this, 200, 200)
this.group.add([a,b])
this.physics.add.collider(this.group, this.group)
//now, the damping doesn't work
2

Alright so groups change the body’s values to default even if there already is a body, so all I had to do is change the order of setting body settings and adding to group.

this.a = new Being(this, 50, 50)
this.b = new Being(this, 200, 200)
this.group.add([a,b])
this.a.setDragX.....