Kaltura_Client_Exception thrown

Invalid KS "MjY2M2Q0ODNhNDMxODgzNDdiNzg1MjRjNWY1NjQzMDAzMWU5ODc0M3wxMDE7OzE0NzUxNTIwODQ7MjsxNDc1MDY1Njg0LjI1ODY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"