Hi
As mentioned in properties (Analysis Type) you need to set it to 3D as beam/lines will not work with 2D option.
To have 2D in the 3D analysis then just fix the Z - direction on all nodes and the ROTX and ROTY.
Set a snippet with:
D,ALL,UZ,0
D,ALL,ROTX,0
D,ALL,ROTY,0
That makes it 2D in principle
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