Concepts
Three ideas come up in every e-invoice guide, and a reader who meets them for the first time halfway through a procedure has to stop and infer them. They are explained once, here, so the guides can get on with the task.
One tax document standing in for thousands of retail receipts — and the RM 10,000 line it cannot cross
A pool holds a document that cannot be sent; a queue holds one that can and is waiting its turn
What LHDN decides, when the 72-hour door closes, and why Submission History is not a status
Read them in that order if you are new to this. If you only read one, read pools and queues — when an e-invoice seems stuck or late, the first thing to find out is which of the two the document is sitting in.