The metal handle that we grip to unzip the zipper may sometimes break or fall off due to wear and tear.

To install a thin piece of cloth in lieu of the handle, raise up the area where the handle is fastened with a screwdriver.
3. A jammed zipper

There are many reasons why a zipper might get stuck, but the most common solution is to sandwich some lip balm or Vaseline between the teeth of the zipper.

This ought should be sufficient to release a trapped hinge.
4. Lost or extracted teeth

Cutters, adhesive, and a cotton swab are required. Cut the cotton swab's plastic tube into tiny pieces.

Grab a piece, cut open one end, and press it against the area where the tooth is gone.