e-Invoice transmissions accumulate daily. A mapping error in buyer identifiers or tax codes does not announce itself at month-end; it sits in the portal as a population of applications that later filings will inherit.
A modest sample—issued and received, including credit notes—run each month is cheaper than a reconstruction after a query. Trace a handful of documents to source invoices. Write down who can change a mapping and who reviews a failed transmission.
Seremban manufacturers and service firms we meet often have a capable tax agent and no one assigned to the trail. The agent files. The trail still belongs to the company.