I would say the Floor Plan Display for your door is set to "Projected" or "Projected with Overhead".
This will be giving you a projection of the 3D view in plan.
So if your door is closed in 3D it will be closed in plan regardless of the 2D opening setting.
Try setting your door to "Symbolic" then you will see it in 2D as it was intended.
You can then play around with the "Detail" settings depending on what level of detail you want to see for the door and frame.
Unless you are using the Floor Plan Cutting Plane settings to manipulate the plan view of your elements I would leave everything (walls, columns, doors, windows, etc.) as "Symbolic" so you have less to worry about.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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