adsorption of charged molecule on surface

Dear Professor Nick,

 For the adsorption of charged molecule on surface, if we added the net charge in the fdf file and we received the warning that the Madelung correction is not calculated. So, our calcuation without this Madelung correction is corrected and the final energy is taken an accound this charge or our calculation is like the adsorption of a neutral molecule on surface.

Please explain me this point.

Please answer me.
Thank you very much in advance,