Fit of data recovered from file .sfit

I have done curve fitting a few months ago. Saved my session as sfit. I recovered the x and y from the .sfit file using the command

v = load('attenuazione sodio.sfit', '-mat');

[x,y] = v.savedSession.AllFitdevsAndConfigs{1}.Fitdev.FittingData.getCurveValues;

At this point, using the information contained in the file sfit, I would like to fit the data again and make a plot of the type (myFit, x, y). How can I do it ?