Kaltura_Client_Exception thrown

Invalid KS "Yzg1NTM5MWVmZDQ3Y2Q1MzE0YzAzYjI0NDc0ZWI4ZTg4NGJhZDA3ZXwxMDE7OzE0NzQ5NDM2MTI7MjsxNDc0ODU3MjEyLjA4MjQ7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"