A hole punch that receives a lot of use can become locked up. Most often, one of those little paper discs gets lodged in the punch mechanism, causing the lever to no longer operate and jamming the paper punch. Fortunately, it is very easy to not only clear a jammed hole punch but also maintain it so jams occur a lot less often.
Open the bottom catch tray and clear out any paper discs. You may want to do this over a trashcan to avoid getting paper all over the place.
Dislodge any stuck paper discs. Taking the eraser end of a pencil, check each of the punch heads and push out any stuck paper, paper dust or jammed punch-head springs. If a spring is stuck, a light push with the eraser should snap it back into place.
Replace the paper catch tray and move the hole punch lever to make sure the punch heads are moving smoothly.
Lubricate the hole punch. To prevent the hole punch from locking up in the future, make a few punches in a piece of wax paper to lubricate the hole punch.
Sharpen the punch heads. Punch a few holes through a piece of aluminum foil to sharpen the punch heads.
Clean the hole punch. To remove any excess wax or metal shavings, finally make a few punches through a piece of card stock.
In lieu of wax paper, you can also use a piece of card stock rubbed with dry soap to lubricate the paper punch.