Kaltura_Client_Exception thrown

Invalid KS "MGNmNDc4OWNmZmRhYmNmNzQ2ZGIxNDQwMTI1MzY2OTU3Yzc3MGFlMnwxMDE7OzE0NjcyNzgzODY7MjsxNDY3MTkxOTg2Ljc1OTg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"