Some customers have inquired if it is possible to stop a glow stick from activating once part of it has been cracked/activated. The short answer is no. Unless you want to snip off the ends that were cracked and have a safe way to plug the open ends–there is not way to stop a glow stick once it has been activated.
However, you can slow the chemical reaction by placing the glow stick in the freezer. If you have received dead glow products from the store then you should return them immediately for a refund.