Kaltura_Client_Exception thrown

Invalid KS "YTdkYTc4NGJkNjIzYWRhMGI2MzgxYjRjZWNmZjEyODViODM5N2Q0ZXwxMDE7OzE0ODUzNjUwNDk7MjsxNDg1Mjc4NjQ5LjE3NzI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"