Kaltura_Client_Exception thrown

Invalid KS "OWNmNWUxMmRiNmQwYWQ5NTU4ZTNhZmRhZTQ2MGY3ZTQwZjQyN2QwNHwxMDE7OzE0ODgwMzU4NjI7MjsxNDg3OTQ5NDYyLjY5Njk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"