the_ID & wp_get_attachment_image_src(the_ID(), “medium”) blank

by

I changed to:

 $attch_id = get_post_thumbnail_id( $my_query->post->ID );
 $thumbnail_arr = wp_get_attachment_image_src($attch_id, "medium");
 $thumbnail = $thumbnail_arr[0];

and $thumbnail is returning what I want now.