Kaltura_Client_Exception thrown

Invalid KS "MWNlZjk1MWQ3OTNjN2JhN2I2MGMxY2U0N2NhMjM0Mzk5MWM4ODA5ZXwxMDE7OzE0NzUyMzgzMjg7MjsxNDc1MTUxOTI4LjQxMjE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"