Rectify first, then find the cause
The immediate response is to get the area right, and that usually happens on the next attendance or sooner where the issue affects use of the building. But rectification is the easy half. The harder half is establishing why it happened, because the same gap will produce the same report next month if nobody looks. A missed area is almost never simply forgotten. Treating it as forgetfulness guarantees the same report arrives again next month.
The common causes are dull and identifiable. The area was locked. The area was occupied. The shift ran out of time because something else took longer. The cleaner was covering and did not know the area existed. Equipment failed. Each has a different fix, and none of them is addressed by rectifying the area and moving on to the next thing. Naming which of those applied is the whole of the investigation on most occasions.
