Do all the walls (reference lines) trim properly to form a closed boundary or are there gaps?
Are you getting a message to say that the boundary can not be found or any other kind of error message?
Does it work if you use the manual boundary and magic wand to flood the room area?
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11