ShapeAnalysis_Curve and GeomAPI_ProjectPointOnCurve returns point with wrong Z-coordinate

Hi,
I have an edge, which is basically 1/2 of a circle. It is located at the plane Z = 1.0
When using both cited methods with bounds (0 to PI) they both return the correct x ynd y coordinates.
The z coordinate, however, is translated by 1.0, at z=0.

Am I missing something here? This happens with a geometry created within the same cpp file.
If I export and read the same geometry as an IGES file the projection works.
It seems exporting corrects something in the TopoDS_Edge object, that was not done when working on the object.

The code used:

Handle(Geom_Curve) a_curve;
TopLoc_Location loc;
Standard_Real first_u = 0;
Standard_Real last_u = 0;
a_curve = BRep_Tool::Curve(TopoDS::Edge(an_edge), loc, first_u, last_u);
gp_Pnt new_pnt;
Standard_Real param = 0;
auto var = GeomAPI_ProjectPointOnCurve(a_pnt, a_curve, first_u, last_u );
auto nbpnt = var.NbPoints();
auto pnt = var.Point(1);
const Standard_Real projected = ShapeAnalysis_Curve().Project(a_curve, a_pnt, Precision:.Confusion(), new_pnt, param, first_u, last_u, false);