this type of damage ,is normally caused ,either by a heavy landing after a fall from say a tree ,because the motors have stopped or because the antenna has hit a solid object like a wall or tree trunk, the main problem afterwards ,is the unseen damage that may have happened to the end of the arm where it swivels or to the wiring to the antenna or light if all that is ok then fitting a new landing leg /antenna housing would be restoring the drone to full health ,just gluing it back would only be a temporary fix till a new part could be obtained ,the other way to do the repair would be to change the whole arm complete with motor antenna and light , this would require some soldering skills and the drone would need to be opened up to achieve this, this of course would invalidate the care refresh, so in this case it would probably be best to send it in for a refresh claim