BUG detected on tuple strings of a portal

[sunrise125]

Reference is made to such an application: https://www.ritchievink.com/blog/2017/03/12/python-1d-fem-example-3/ The following commands: print(ss.get_node_results_system(node_id=2)) print(ss.get_node_results_system(node_id=3)) produce {'id': 2, 'Fx': 3.019806626980426e-14, 'Fy': 5.329070518200751e-15, 'Ty': 2.842170943040401e-14, 'ux': -0.06264606770288353, 'uy': 0.0037928468734012145, 'phi_y': 0.01282309350473621} {'id': 3, 'Fx': -2.1316282072803006e-14, 'Fy': -0.0, 'Ty': 7.105427357601002e-15, 'ux': -0.057540201133450423, 'uy': 0.012873819793265443, 'phi_y': 0.002160511813039763}

where bending moment at node-2 Ty should be 23.9, not zero (2.8e-14), same story at node-3, Ty must be 44.2 instead of zero (7.1e-15).

Could someone be so kind to let me know the reason? Thank you