Kaltura_Client_Exception thrown

Invalid KS "MWQ4YTk5ZDNhNzgwNzFlNDZkMGZjNTQzMTA0ZTYzNzA2ZTBiOTRjY3wxMDE7OzE0ODUzMDc4Mjg7MjsxNDg1MjIxNDI4LjQ5MjE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"