Beaky beat me to it but......

No. 1 - never ever put WD40 or anything like it on your machine, especially on the plungers (rods that go into the coils).

No. 2 - see No. 1.

You will be better off pulling the flippers apart now and removing the WD40.  It will work short term but then as it gets dirty it will gum up and makes things 10 times worse than what you started with.

In relation to the flipper not staying up (I am guessing this is what you mean by out) my first thoughts would be that the hold wire (the very thin fine one) on the coil may be broken.  I can't remember what coils are in Addams but check the very thin wire on the coil, if there is one.

The only time you should put any type of lube on or in a pinball machine is where you have metal rubbing or meshing together on metal.