What's up blades? The title basically explains everything, there's dirt in it.... Someone found out I had it so I had to hide it...
Is it actually DIRT? Like earth matter? If so, hot water should be able to clean that right out. If it's resin, than isopropyl alcohol will work. Pour it down the top of the bong, than blow on the mouthpiece to force it up through the perc and back down to the bottom chamber.
Wash out with warm/hot-ish water first, like I said, fill up the top part, than blow in the mouthpiece to force water through the perc back into the bottom chamber. Do that a few times until the dirt is gone. Than do the same thing with the rubbing alcohol, it may need to sit a bit, unless you can figure out a way to agitate it.