@blanchsb I eyeballed it but if you want to be more precise , with the loop tools add-on loop select a ring of verts and click on circle ( loop tools add-on), for the top squarish part I would vertex snap to line up with the others. I see now on @spikeyxxx ‘s post , I didn’t include that edge when I scaled out . But I would say more geometry is required or at least one edge loop as @spikeyxxx has done on that face to define the shape.
