Administrative Appeal Act Article 44

To serve the one without capacity to undertake any administrative appeal conduct shall be made to her/his legal representative, while the legal representative is not stated to the agency with jurisdiction of administrative appeal, the service might have made to the one without capacity to undertake any administrative appeal conduct.To serve a legal entity or organization shall be made to its representative or administrator.While there are more than one legal representatives, representatives or administrators, the service might have made to one of them.
中文原文 訴願法第44條
對於無訴願能力人為送達者,應向其法定代理人為之;未經陳明法定代理人者,得向該無訴願能力人為送達。
對於法人或非法人之團體為送達者,應向其代表人或管理人為之。
法定代理人、代表人或管理人有二人以上者,送達得僅向其中一人為之。

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