The validity of any special tax levied under this code shall not be contested in any action or proceedings unless the action or proceeding is commenced within thirty days after the effective date of any ordinance or resolution providing for the levy of such special tax. Thereafter, a special tax may be contested only for the purpose of challenging the accuracy of computation of the special tax. Any appeal from a final judgment in the action or proceeding shall be perfected within thirty days after the entry of judgment. (Ord. 2241 NCS § 4, 2006; Ord. 2119 NCS § 2 (part), 2001.)