BRep_Tool::Triangulation return null

Hello, I've tried to get the Poly_Triangulation from every face of my shape, but for 2 faces it return a null triangulation... I created the shape with makePrism and I can't get the Poly_Triangulation of 2 the profile faces. I think the problem is in the prism building , because with other shapes the triangulation works. Thanks for your attention.

This is my code:

Handle(ShapeExtend_WireData) edges = new ShapeExtend_WireData();
for (TopTools_ListIteratorOfListOfShape iterator(listOfEdge); iterator.More(); iterator.Next()){
TopoDS_Edge currentEdge = TopoDS::Edge(iterator.Value());
edges->Add(currentEdge);
}

//create a ShapeFix_Wire to be sure that all edges are in order, connected and create a closed wire

ShapeFix_Wire fixWire;
fixWire.Load(edges);
cout fixWire.FixReorder();
fixWire.FixConnected(); //to ensure vertices are shared btw edges
fixWire.FixClosed();
TopoDS_Wire profileWire = fixWire.WireAPIMake();

//I use GProp_PEquation to be sure that my edges are coplanars
//coplanarPoints is the points array I used to create the edges
GProp_PEquation peq(coplanarPoints, 0.1);

//I use the mean plane to create the face
BRepBuilderAPI_MakeFace mkFace(peq.Plane(), profileWire);
printf("mkFace error: %d\n", mkFace.Error());
TopoDS_Face myFaceProfile = mkFace.Face();

//extrusion vector
SbVec3f profTrans = profileTranslation->translation.getValue();
gp_Vec extrusionVec(profTrans[0],profTrans[1],profTrans[2]);

BRepPrimAPI_MakePrism mkPrism(myFaceProfile , extrusionVec, true);
//printf("mkPrism error: %d\n", mkPrism.Error());
TopoDS_Shape myShape = mkPrism.Shape();

BRepMesh_IncrementalMesh MESH(myShape,deflection);
TopExp_Explorer ex;
for (ex.Init(myShape, TopAbs_FACE); ex.More(); ex.Next()) {
const TopoDS_Face& aFace = TopoDS::Face(ex.Current());
TopLoc_Location aLoc; //è una transizione composita
Handle(Poly_Triangulation) aPoly = BRep_Tool::Triangulation(aFace,aLoc);
if(aPoly.IsNull()) error++; //for 2 faces I have a null triangulation
else { //continue
...
}
}