Ultimate Facebook events listing vanishes after 24 hours or less

I have managed to get the Ultimate Facebook plugin to work. Done all the API creation etc and I'm using this shortcode:
[wdfb_events for="idNumberHere" only_future="true"]

on this page:
http://widows666.co.uk/venues/

The problem is that the events keep vanishing from the page. If I login and update the page without changing anything at all then the events will appear again but then disappear after about a day.

I really need this issue solving please.