[UnGodly]

Your code should be

PHP код:

DeletePlayer3DTextLabel(playerid,Text3D:onduty); 


instead

PHP код:

Delete3DTextLabel(Text3D:onduty); 


You were creating a 3d text label only for a specific player.

https://sampwiki.blast.hk/wiki/CreatePlayer3DTextLabel
https://sampwiki.blast.hk/wiki/DeletePlayer3DTextLabel
https://sampwiki.blast.hk/wiki/Delete3DTextLabel