RepositoryException: org.sql2o.Sql2oException: Database error: No results were returned by the query

Question

I am using postgres sql as database and java for backend. I am using sql2o with java code as shown below.

public Category insertCategory(Category category) {
        // TODO Auto-generated method stub
        System.out.println(category.getName());
        String query = getQuery("insertCategory");
        try (Connection conn = getConnection()) {
        conn.createQuery(query).bind(category).executeAndFetchFirst(Category.class);

            return null;
        }
        catch(Throwable t) {
            throw new RepositoryException(t);
        }
    }

Category class is a model which contains properties like name,description,title.

public class Category extends Entity {
    private long id;
    private String name;
    private String description;
    private String title;
}

Query :

insert into category(name, description, title, icon) values(:name, :description, :title, :icon) returning * 

i am using returning * to get back the inserted records as shown above. But i am getting the following error

com.hiya.repo.utils.RepositoryException: org.sql2o.Sql2oException: Database error: No results were returned by the query.
    at com.hiya.repo.orientdb.CategoryServiceImpl.insertCategory(CategoryServiceImpl.java:70)
    at com.hiya.repo.orientdb.TestCategoryServiceImpl.testInsertCategory(TestCategoryServiceImpl.java:66)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 

Am i going wrong somewhere ?