Postal Act Article 35

Once the amount of compensation is settled, notice must be given to the recipient of the claim. If not exercised, the recipient’s right of indemnity shall be extinguished five years from the date the notice is served.
中文原文 郵政法第35條
補償金確定後,應通知受領補償人。
補償金請求權,自受領補償人收到通知之日起,逾五年間不行使而消滅。

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