Check the layer combination that is saved with the schedule view.
If the layer is hidden the window will still show in the schedule but it will be locked, and the select in 2D/3D icons will be greyed out.
If the layer is locked then the window in the schedule will also be locked but the select in 2D/3D icons will be available.
So if you are using saved views to switch between your schedule and plan, this could be why your plan looks OK but the schedules is locked.
They may be using different layer combinations and some of the layers in your schedule may be hidden.
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