There is an error fixing DOFs of pfacet?

Hello,

I want to fix the rotation DOF of a pfacet. But when I tried that, the face disappeared in the GUI. I used inspect to check the state of the facet. It said nan for some values (pos, vel). Can you help me find a way to contrain the motion of a pfacet. The minimum working code is given below,

Regards,
Rohit

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from yade.gridpfacet import *

O.engines = [
        ForceResetter(),

        InsertionSortCollider([
            Bo1_GridConnection_Aabb(),
            Bo1_PFacet_Aabb(),
        ]),

        InteractionLoop(
            [
                Ig2_PFacet_PFacet_ScGeom(),
                Ig2_GridConnection_GridConnection_GridCoGridCoGeom(),
                Ig2_GridNode_GridNode_GridNodeGeom6D(),
                Ig2_GridConnection_PFacet_ScGeom(),

            ],
            [
                Ip2_FrictMat_FrictMat_FrictPhys(),
                Ip2_CohFrictMat_CohFrictMat_CohFrictPhys(
                    setCohesionNow = True,
                    setCohesionOnNewContacts = False
                    ),
            ],
            [
                Law2_GridCoGridCoGeom_FrictPhys_CundallStrack(),
                Law2_ScGeom_FrictPhys_CundallStrack(),
                Law2_ScGridCoGeom_FrictPhys_CundallStrack(),
                Law2_ScGeom6D_CohFrictPhys_CohesionMoment(),
            ],
        ),
        NewtonIntegrator(gravity = [0,0,9.81], damping = 0),
    ]
O.materials.append(CohFrictMat(young=1e7,poisson=1,density=1e2,frictionAngle=radians(30),normalCohesion=3e7,shearCohesion=3e7,momentRotationLaw=True,label='gridNodeMat'))
O.materials.append(FrictMat(young=1e7,poisson=1,density=1e2,frictionAngle=radians(30),label='gridConnectionMat'))

node_id_list = []
cyl_id_list = []
pfacet_id_list = []
pfacetCreator1(
                [
                    [1,0,0],
                    [0,1,0],
                    [0,0,1]
                ],
                radius = 0.05,
                wire = False,
                fixed = False,
                color = [0.5,0.5,0.5],
                materialNodes = 'gridNodeMat',
                material = 'gridConnectionMat'
                )

for i in O.bodies:
    i.state.blockedDOFs = 'XYZ'

O.dt = 1e-6
O.saveTmp()
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