Direct answer
A missed room can be blocked by a threshold, closed door, no-go zone, weak map connection, dark floor or insufficient battery to reach it.
What this covers
- Robot vacuums · mapping
- The exact symptom in the title before component-level repair
- Consumer-accessible controls, connections and maintenance areas
What it does not cover
- ×Smoke, burning odor, swelling, liquid on powered parts or damaged wiring
- ×Opening sealed panels, bypassing interlocks or live-electrical testing
- ×Account ownership, billing or warranty disputes
Observe before changing anything
ReversibleWatch the robot approach the doorway and inspect map boundaries and excluded zones.
Isolate the failing boundary
ReversibleRemove temporary obstacles, improve lighting if required and test from inside the room.
Apply the narrow correction
ReversibleEdit the map or threshold setup before deleting the entire map.
Verify the result and stop at the boundary
ReversibleDo not force the robot over a threshold outside its clearance specification.
Evidence ledger
Sources behind this answer
Visible sources support the visible claims. Home Product Support records the publisher, the fact used and the review date; community reports can suggest an issue but do not become a published fact on their own.
Exact questions
Common follow-ups
What should I check first for “Robot vacuum will not enter or clean one room”?+
Watch the robot approach the doorway and inspect map boundaries and excluded zones.
How do I know whether the problem is external or inside the device?+
Remove temporary obstacles, improve lighting if required and test from inside the room.
When should I stop and request repair?+
Do not force the robot over a threshold outside its clearance specification.
Answer for the exact device and software version shown above.