Meshed shell model reactions.

[KonstantinUdilovichWSP]

I have a meshed plate with a single point load at a node. I am getting the summation of reactions greater than the point load magnitude.

Details: I have built a meshed 2D slab using TriangleFlatShell elements. I have applied dx, dy, dz constraints to multiple nodes.
A single point load is applied like this:

feaModel.Nodes[20].Loads.Add(new NodalLoad(new Force(0, 0, -5000, 0, 0, 0)));

After I solve the model, I extract the reactions:

        var reactions= feaModel.Nodes.Select(n => n.GetSupportReaction()).ToList();
        var nonZero = reactions.Where(f => f.Fz > 0).ToList();
        var sum = nonZero.Sum(f => f.Fz);

The value of the sum is: 14414.46

Are there any known issues with TriangleFlatShell element? How can I troubleshoot this?

Correction: there's an error in the query above, since it filters out negative reactions