circle runs long and never stops

Hi there,

Thanks for this great plugin, it is exactly what I need. I am using it with even manager and I need to have rating for events.
The problem is the waiting circle runs long time and doesn’t stop. I guess there is a conflict with some other part of code however I am not sure how I can fix it. I think removing the plugin and installing it again may solve the issue, but it looks like the data stays there when I uninstall and install it again. Do I need to remove the related table in database?

Tanks again,
Sara