Cal. Lab. Code § 2058

At least 30 days prior to the expiration of each registrant’s registration, the commissioner shall mail a renewal notice to the last known address of the registrant. However, omission of the commissioner to provide the renewal notice in accordance with this subdivision may not excuse a registrant from making timely application for renewal of registration, may not be a defense in any action or proceeding involving failure to renew registration, and may not subject the commissioner to any legal liability.