The current 8-digit serial number in the businessMessageId is a daily running counter, resetting to zero each day. While it supports up to 99+ million messages per day, the growing adoption of DuitNow products and rising transaction volumes have pushed this limit.
 

As a result, the 8-digit range is no longer sufficient to guarantee unique identification for every message within a single day.
 

To manage this, participants can use transaction type and channel code alongside the businessMessageId to ensure uniqueness.
 

This limitation has been acknowledged and is under active review for inclusion in a future core switch update, as part of PayNet’s commitment to continuous improvement and scalability.