Please provide page link where you want to have a button and the screenshot of the button place on it’s page you tried and want to make Live Chat on click. Thus I can take a look to it’s code and help you.
I went to the page link you have provided, clicked on the button at the bottom of the page and Live Chat appeared – http://prntscr.com/fb1rh8
Is it what you wanted?
If you can’t see the live chat try to clean cache in your browser and if you use cache plugin also clean cache in it.