Two methods to try 1 you can put screw back into the plug just enough to grip plug and not re expanding plug behind the tile then gently pull out with pliers hopefully bring screw and plug out together.
How to remove wall plugs from tiles.
Or if that fails 2 drill it out using smaller bit than hole and clear debris out of hole a bit messer and a butchers job but it works.
Don t worry getting them out is an easy job.
Push the anchor through the wall with a screwdriver.
They seem to be every where no wall seems complete without one.
After pulling a 4 inch circle of plaster out of the wall i developed a method of holding the plaster in place whilst pulling a rawlplug out.
Another option is to place a phillips head screwdriver in the anchor.