Regulations Governing Institutions Engaging In Credit Card Business Article 52

To protect the interests of cardholders, a credit card business institution shall establish a complaint handling procedure and set up a complaint and service hotline. It shall also post the service hotline on the back of the card, and notify the cardholders of such information in writing or by electronic document and post the same on its website.Unless the filing of information is waived by the Competent Authority, a card issuer shall, before filing the information on late payment by a cardholder that is more than one month overdue, compulsory suspension or closing of card account, receivable on demand, bad debt and other bad credit record of a cardholder with JCIC, notify the cardholder of the reason for filing the bad credit record with JCIC and possible effects on the cardholder in writing or by electronic document as agreed with the cardholder in advance.
中文原文 信用卡業務機構管理辦法第52條
發卡機構應訂定信用卡申訴處理程序及設立申訴與服務專線,且應將該專線記載於卡片背面,並以書面或電子文件通知持卡人,另於所屬網站公告,以保障持卡人之權益。
除依主管機關規定免報送資料者外,發卡機構將持卡人延遲繳款超過一個月以上、強制停卡、催收及呆帳等信用不良之紀錄登錄於聯徵中心前,須將登錄信用不良原因及對持卡人可能之影響情形以書面或事先與持卡人約定之電子文件告知持卡人。

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