Kaltura_Client_Exception thrown

Invalid KS "MmExMTliMmY1MTRlYmY5ZTE4YzI4NDc0MzRlODlkMDg0YjMyODllNnwxMDE7OzE0OTU4MDE2MTk7MjsxNDk1NzE1MjE5LjM1Nzg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"