Sometimes when you are stuck, you are stuck because you are trapped in your opinion of what your writing should be like. I know this may sound funny, but it is true.
You have an idea about what your writing should look like, and that is not happening. So you feel stuck.
What if you threw out the rules? What if you let go of your beliefs about what you are writing about and simply looked at it in a different way? You may be stuck because your idea or concept, just doesn't work. What if you threw it away, and, for the time being, you explored some new possibilities. (You can alway pull your play from the trash.)
But what if you tried writing a "paralell" play? A play that is happening around this play? Or nearby?
What if you wrote an "opposite" play? Same place and time but the action is completely opposite to what you had in mind?
What if you wrote your play as a fairy tale? Or as a Sci-Fi play? Or set it in the 1950'S! See what I am doing? Mess with your IDEA of your play and something else might manifest, or even better, you may discover something that will propell your original idea into a new exciting place.
So don't be afraid to throw away ideas, concepts, settings and even your play - and see what manifests!