Impossible to tell what is wrong, given this little information.
It smells like different JS files being loaded in the <head> of the two pages. You should load the same JS in every page <head> or else use something like require.js if you want to defer loading of scripts.
Maybe you forgot something? I mean you forgot to post an example and/or your code here... We aren't mind readers, not sure how I can help from this. Please get something together that we can actually use to help you and then come back.