When I turn off the inner boundary line to turn the finish wall inside, a line like that comes out?

[LeeJaeYoung]

can you erase it?

[Laurentiu · Accepted solution]

You can, just untick this and only one single line should be displayed.

[LeeJaeYoung]

I thought it was the same concept as this, but it's a different concept. Thank you. ^^