Enforcement Rules of the Labor Pension Act Article 28

For employers who notify and apply with the Bureau for ceasing the contributions to labor pension in accordance with Article 18 and Paragraph 1 to Article 20 of the Act, the portion of voluntary contributions shall also cease.
中文原文 勞工退休金條例施行細則第28條
雇主依本條例第十八條及第二十條第一項規定申報停止提繳退休金時,勞工自願提繳部分即同時停止。

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