Okay, the code is fixed and running fine. Please check this screenshot:
http://prntscr.com/oc2so1
Now you can check the site.
The code was not working because of the two reasons:
1) The script tag is missing from the code which I have added already.
2) The ID was called was wrong, as you have told that this your staging site.
I have written the code according to the code written in this site.
It might or might not work for your original site.
In case it doesn't, please share original site URL, I will update the code for that as well, then it works fine.
Good Day