The absolute best Way to Clean resin out of a glass pipe is described below. This is based on having the same experience you’re asking about.

Let me list the steps to take so you can get your glass clear of resin.

  1. First, use a tool like an X-Acto Knife to scrape off as much of the resin as possible without scratching the glass. Skip this step if the resin has solidified.
  2. Then, find yourself a wide Pyrex bowl with a flat bottom. The bowl should be made of glass. The flat bottom is required for the glass pipe to sit flat underneath the solvent I’ll describe in my next point.
  3. This point is important. Find a source of 99% Isopropyl alcohol. Amazon sells it. Don’t use regular rubbing alcohol from from your local drugstore. That’s not as strong as you’ll need it to be.
  4. Pour enough of the 99% alcohol into the Pyrex bowl to completely cover the glass stem you’re trying to clean. Move it around a bit to make sure there are no air bubbles inside of it.
  5. Wait 24 hours for the solvent to work.
  6. By the following day, your glass pipe should look like new!

Also you can try this 

 

       Instead of a pyrex bowl, seal the piece to be cleaned in a plastic ziplock sandwich bag. Also add salt. The plastic bag allows you to agitate the piece without risking breaking it (or spilling anything) and the salt acts as a mild abrasive to help loosen any tough bits of resin without being hard enough to damage the glass itself. Work as much of the salt in through the holes of the pipe as you can, then give a few solid minutes of shaking it all around in the bag. Once it's clean, give it a nice long rinse under warm water

 

and this is for you want to use some home prodcuts.

a few drops of DAWN dish detergent and a few tablespoons of rubbing alcohol (the cheap stuff from Walmart or any drugstore) in a glass dish in the microwave to about the temperature of a cup of coffee. Put your glass pipe in it making sure pipe is fully underwater. Soak an hour or so and should be good as new