How to set delegated property value by reflection in kotlin?

My entity class:

class User : ActiveRecord<User>() {
    var name by Column(String.javaClass);
    var id by Column(Int.javaClass);
}

now I want to set name value by refelection:

var clazz = User().javaClass
var record = clazz.newInstance()
var field = record.getDeclaredField(it + "$" + "delegate")

field.set(record, "aa")

then error:

entity.Column field ActiveRecord4k.User.name$delegate to java.lang.String

how to do this?