Kaltura_Client_Exception thrown

Invalid KS "YWI5YTA2YzI5Y2RkMDcwYTMxZTcyY2MxZTRjZDJkNjEyMTQ5MWQyNnwxMDE7OzE0OTU3ODgxMDU7MjsxNDk1NzAxNzA1LjM4ODY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"