The electronic configuration of Fe is 1s2 2s2 2p6 3s2 3p6 4s2 3d6.
So after removing two electrons the configuration becomes:
1s2 2s2 2p6 3s2 3p6 3d6

But why cant the electrons rearrange themselves to give a more stable
1s2 2s2 2p6 3s2 3p6 4s1 3d5 configuration?