Kaltura_Client_Exception thrown

Invalid KS "YzYzYmQ0MGEwMWNjN2EwMjAwZDUzNDJkMWVkMjAzZWQ5MmUxYjY2OHwxMDE7OzE0Njc1MzE3NTg7MjsxNDY3NDQ1MzU4LjcyMDI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"