C++ directx picking is not working

[ramilol]

i got help writing my picking function... but it still doesn't work im not sure if it is because the my function or because of my mesh it is one of them. someone suggest me to draw the ray, i drew my rays it basically followed my cursor(mouse).
here is my code

    BOOL D3dDevice::Picking(HWND hWnd, LPDIRECT3DDEVICE9 d3ddev, CXFileEntity *entity, int z)
    {
        D3DXVECTOR3 v;
        D3DXMATRIX matProj;
        POINT pt;
        D3DVIEWPORT9 vp;
        D3DXMATRIX matInverse, matWorld;
        D3DXMATRIX m;
        D3DXVECTOR3 rayOrigin,rayDir;
        D3DXMATRIX matView;
        D3DXVECTOR3 rayObjOrigin,rayObjDirection, rayDirection;
 
        GetCursorPos(&pt);
        ScreenToClient(hWnd, &pt);
        d3ddev->GetTransform(D3DTS_PROJECTION, &matProj);
        d3ddev->GetViewport(&vp);
 
        d3ddev->GetTransform(D3DTS_VIEW, &matView);
 
        // Use inverse of matrix
        d3ddev->GetTransform(D3DTS_WORLD, &matWorld);
        D3DXVECTOR3 vec3( pt.x, pt.y, 1.0f );
        D3DXVec3Unproject( &rayObjSpace, &vec3, &vp, &matProj, &matView, &matWorld );
        // Transform ray origin and direction by inv matrix
 
        D3DXMATRIX invWorld;
        D3DXMatrixInverse( &invWorld, NULL, &matWorld );
 
        D3DXVECTOR3 camObjSpace;
        camPos.x=0.0;
        camPos.y=0.0;
        camPos.z=z;
        D3DXVec3TransformCoord( &camObjSpace, &camPos, &invWorld ); 
 
        rayDir = rayObjSpace - camObjSpace;
 
        BOOL hasHit;
        float distanceToCollision;
 
        if(FAILED(D3DXIntersect(entity->pDrawMesh, &rayObjSpace, &rayDir, &hasHit, NULL, NULL, NULL, &distanceToCollision, NULL, NULL)))
        {
            PostQuitMessage(0);
        };
 
        if(hasHit==1)
        {
            PostQuitMessage(0);
        }
 
        return hasHit;
    }

i have no idea why it is not working, by the way i did a that `rayObjSpace.z` never equals to 0, it is always in the 80s. entity->pDrawMesh is not `LPD3DXMESH` not `LPD3DXBASEMESH`.
thanks in advance