1. Look for fabric stuck in the zipper.
Sometimes, zippers may stop working because some of the surrounding fabric gets caught in the teeth. Inspect the garment or accessory closely for snags, folds, tangles, and other signs of a hangup. These tend to be pretty easy to correct.
Snags are usually to blame when a zipper completely refuses to budge.
If there are no visible obstructions in the zipper teeth, you may need to try lubricating the teeth instead.
2. Pull the fabric away from the zipper.
Once you’ve located the snag responsible for blocking the zipper, take hold of the fabric around the obstruction and give it a gentle tug. If the obstacle is tiny, using a pair of tweezers may help you get a better grip. Next, pull the fabric opposite the zipper run and hold it.
You can also try dislodging the fabric from inside the teeth with the point of a safety pin.
Be careful not to wrench on the fabric too hard, or you may tear it.
3. Work the zipper up and down.
Keeping your hold on the snagged fabric, begin gently pulling the zipper tab. Try sliding it in both directions to see if the fabric releases. In most cases, constant tension, small movements, and a little patience will be enough to clear the zipper teeth.
If you don’t have any luck freeing the fabric from the zipper, your only option will be to take it to a tailor.
4. Prevent further obstructions.
After successfully dealing with a troublesome zipper, take a few precautionary steps to ensure the problem doesn’t happen again. Stitch up ragged holes, smooth out wrinkles and use a razor to cut loose threads. When you’re done, iron the fabric on both sides of the zipper to make sure it lays flat.
The less fabric there is in the way of the teeth, the less likely another snag is to occur.
Keep an eye out for frayed edges around the zipper tape itself.