[Ifeffit] graphics help

Hello help in: why in my graphics the fit curve is more differents that data curve?. If that fit is ok, but the fit curve(red) is very underneath that data curve(blue). Some idea Chachi P.D my graphis is in attachment -- Chachi Rojas GMC FCF UNMSM Tel.Mo.:97499347 email:crojasa@unmsm.edu.pe