How to remove a stuck downstem should be in the manual of every bong.

How to remove a stuck downstem should be in the manual of every bong.
Letting the stress of fixing this issue and getting to your next smoke session can make it seem even more imperative. If rushed, forcibly, and incorrectly removing the downstem could lead to a disaster, like a broken downstem!
You can prevent this by removing and cleaning the downstem even when it is in perfect condition.
A long cylindrical tube effectively seals the bong, allowing the smoke to flow into the chamber without dispersing. Your downstem can get stuck because of various reasons like resin build-up or incomplete drying after cleaning.
The most effective way to prevent your downstem from getting stuck would probably be cleaning your bong every single day.
If you have the time to wait for two days and are not in dire need of a good rip, then using a glass cleaning item specific for bongs and bowls may be the right thing for you.
These methods involve applying the cleaner to the downstem and joint and simply waiting for everything to absorb into the build-up on the glass pieces long enough to become easily removed.
If you have a graphite stick specific to cleaning bongs and bowls, you can easily push this into the downstem opening. From here, you would add a little twist of the wrist and gently wriggle, and you will be able to pull your downstem out to safety.
You Have Only Household Items,can use simple household items, such as things that vibrate like an electric toothbrush or razor. For safety, wrap the item in a cloth or napkin and gently press the vibrating object along the joint of the bong where the removable downstem piece comes out.
Since you may be tipping the bong at an angle downward to help remove it, it is probably a good idea to have someone or something ready to hold and catch the glass stem as it loosens.
Another option is trying rubbing alcohol which is cheap and widely available. Pour rubbing alcohol where the downstem is stuck and use a toothpick to loosen the space between the downstem and the glass slowly. Some people even try using WD40 instead of alcohol, but thorough and proper cleaning after freeing the downstem you will need to remove any remaining toxic chemicals and residue.