The walls probably aren't locked - they will be grouped.
Locked items have grey coloured handles when you select them and you will get a warning message they are locked.
Grouped items have coloured circles for selection handles instead of small black dots.
You can ungroup (CTRL+SHIFT+G) the elements - this is a permanent change.
Or you can use the "Suspend groups" to to temporarily separate them.
"Enable groups" to set them back as one element.
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