The Enforcement Rules of the Specifically Selected Goods and Services Tax Act Article 26

The time limit referred to in Article 20 of the Act for a manufacturer to achieve compliance or take corrective action upon notification of the competent tax authority may not exceed 15 days counting from the day following the date on which the notice is served.
中文原文 特種貨物及勞務稅條例施行細則第26條
本條例第二十條所定主管稽徵機關應通知補辦或改正期限,不得超過通知送達之次日起算十五日。

English translation for reference only; the Chinese text prevails. Not legal advice.