I usually soak my tip in a cup of hot water when I am done using the glue. Then I run warm water over/thru the tip and blow thru the screw on top end out the tiny hole until I can feel air. I keep the original screw top to my bottle on my bottle when not in use. Then I let the tip dry before placing it in a sandwich bag for storing until my next use. I have been doing this for several years.
I too am a fan of Sharon Schambers methods.
You could try soaking yours in very hot water for a while and it should disolve. After all it is water soluble. Good luck.