Not all printer inks will stay on fabric. You might need to buy a product called Bubble Jet. But first I would try this. This is what I do set the ink from my Epson printer. I tried the fabric softner method and it didn't work either. This works for me.
after printing, remove it from the paper, let it dry for about 20 minutes, iron it ALOT, then iron it alot again. Be careful not to scorch. You might want to protect your ironing surface and iron by using a scrap of material under your printed piece and on top of the printed piece. Let it cool for about 20 minutes, soak in a baking dish with a about 2 inches of white vinegar for at least 20 minutes. remove from baking dish, DO NOT WRING OUT EXCESS and lay on a towel. lay another towel on top and lightly press. let air dry, iron it alot again.