Make sure it's loosely planted and the roots are tacked down. Sword plants don't need alot of light to grow. And potting soil (looks like what you are using) probably will not work for swords. It will pretty just kill the plant. Loosely planted and low light should do it some good. If you have a 2 liter bottle, cut the top off put some rocks of gravel in the bottom maybe try a fertilizer tab under the plant and add your plant and water then cover the top with the piece you cut off, sliding it over the other piece. If you have to, tape the area that is cut. Then put it in the window. Low light.