if I change the text in call to action field, the changes will be saved. but if i remove it from call to action, when i want save changes, Changes can not be saved.
So this is the reason why you can't save empty field. Under String Translation > context=admin_texts_theme_betheme you must remove field responsible for call to action because wpml does not allow to save empty fields.
Comments
so what's the problem exactly? Why you can't remove it?