how to prevent added meta box from being injected with style="position: fixed; top: 56px;" at scroll down

This is my first attempt to customize WordPresss.

I added a meta box like this

function settings_metabox() {
    //register custom meta box
    add_meta_box("mybox-id", "Settings", "settings_callback_function", "blog", "side", "high");
}
add_action("add_meta_boxes", "settings_metabox");

but somehow the div gets injected with style="position: fixed; top: 56px;" when I scroll down; and the meta box jumps to the back of the other meta boxes.

How can I prevent this.