My left upper plug fell out a few days ago-i also have 2 smart upper plugs in that tear duct. I am not sure when the plug fell out but for 2 days i felt fine-i went ahead and had an apt.w/ my Doctor and had him put in another upper plug in that eye on top of the 2 smart plugs. It fell out within a few hours! Is it possible that the 2 smart plugs expanded and conformed to my eye and pushed the other umbrella plug out???