Cal. Rev. & Tax. Code § 45301

Any person from whom an amount is determined to be due under Article 2 (commencing with Section 45201), or any person directly interested, may petition for a redetermination thereof within 30 days after service upon him or her of notice of the determination. If a petition for redetermination is not filed within the 30-day period, the amount determined to be due becomes final at the expiration thereof.