Kaltura_Client_Exception thrown

Invalid KS "MDllZGZkYjFiYTlmNTRiYjc1MjRhM2U2ZDBjNDZlNzNkYjgyOGY1MnwxMDE7OzE0NzUwNTk2Mzc7MjsxNDc0OTczMjM3LjI5OTI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"