Unable to find custom widgets in location select

Hello,

I seem to be having an issue in regards to creating custom Widgets using the ACF: Widget plug-in. As it stands I have worked through the example posted at https://www.directbasing.com/resources/wordpress/advanced-custom-fields-widget/#create-kick-ass-widgets-with-acf by adding in the example widget code into my functions.php file.

When I go to the widget screen ‘Example Widget’ is now an option that I can drag into my sidebars, however when I amend any of my ACFs and try to set a rule to display these fields inside the custom widget I have no option to select it, as can be seen here, https://s31.postimg.org/4q82yp7ez/example.png

Any help on this would me much appreciated.

https://www.ads-software.com/plugins/advanced-custom-fields-widget/