What should I do if my Zippo is leak?

If your Zippo lighter is leaking, usually, it is because you filled too much fuel, and the cotton can not absorb it. Another possibility is there might be some tiny objects/dirt between the shell and the insert, which makes a gap.
If you overfilled the lighter, you can take out the cotton, squeeze out some fuel or replace the cotton.
If the cotton does not resolve the problem, consider cleaning the shell and the insert.
And now is the advertising time XD:
If all these are not working, this product may help - a rubber pad outside the felt pad that helps seal the insert.
This pad can decrease leakage dramatically.
And it allows you to carry an extra flintstone with it. 

Click here to purchase.