Well this is unfortunate (carnage)

[OhReely]

Not familiar with that particular reel but if it's a plastic body and the gear is held in place with a self tapping screw then someone probably overtightened the screw and cracked the post at the base where it joins the body. A blunt screw can't go any further into the body so the post climbs the screw. Or the screw/post got cross threaded, jammed and broke the post.