Can't save something in "Theme Options"

Every time when I want to save results in “Theme Options” I have an error “Возникла проблема с Вашим действием. Пожалуйста, перезагрузите страницу или попробуйте позже” (english: “There was a problem with your action. Please reload the page or try again later”). What’s wrong? How can fix it? What information should I give you? Domain: http://loveretour.com/ .