If you are having an issue with Users Ultra Pro and your website the first thing to do is to switch your theme to the default WordPress theme. If the issue/error goes away then you know that there is a conflict between your theme and Users Ultra Pro.
If the error still persists after switching to default WP theme then the issue may be because of a conflict between Users Ultra Pro and another plugin(s). To check for a plugin conflict you need to deactivate all other plugins apart from Users Ultra Pro and see if the issue/error still exists. If the issue goes away then you know there is a plugin conflict. What you need to do then is activate each plugin one by one until you find the plugin causing the issue/error.