Slider GUI for fitting

I want to use slider to determine the lower limit when i try to fit a data, but nothing works. the fitting is appeared but nothing change when i drag the slider. no error message either. i use 'exclude by rule' fitting tool to imply the slider, how do i fix it?

here is the code im working on for callback slider. i was testing the slider feature for popvalue 2 first.

% --- Executes on slider movement.
function slider1_Callback(hObject, eventdata, handles)
% hObject    handle to slider1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
sliderval = get(hObject, 'Value')
assignin('base', 'sliderVal', sliderval)
popvalue = get(hObject, 'value')
file=handles.file
data = xlsread(file)
t1 = data(:,1)
t2 = data(:,2)

if (popvalue == 2)
    [xdata, ydata] = prepareCurveData(t1,t2)
    excludedPoints = xdata < t1.sliderval
    ft = fittype( 'Ms*(1-A/x-B/x^2)+(D*x)', 'independent', 'x', 'dependent', 'y' );
    opts = fitoptions( 'Method', 'NonlinearLeastSquares' );
    opts.Display = 'Off';
    opts.Exclude = excludedPoints
    [fitresult, gof] = fit( xdata, ydata, ft, opts);
    plot( fitresult, xdata, ydata, excludedPoints );
    grid on
    xlabel('H')
    ylabel('M')
    Ms = fitresult.Ms
    a = fitresult.A
    b = fitresult.B
    k = fitresult.D
    set (handles.edit2,'String',num2str(a))
    set (handles.edit3,'String',num2str(b))
    set (handles.edit4,'String',num2str(k))
    set (handles.edit5,'String',num2str(Ms))
    


    
elseif (popvalue == 3)
    [xdata, ydata] = prepareCurveData(t1, t2);
    ft = fittype( 'Ms*(1-A/x-B/x^2)', 'independent', 'x', 'dependent', 'y' );
    opts = fitoptions( 'Method', 'NonlinearLeastSquares' );
    opts.Display = 'Off';
    [fitresult2, gof2] = fit( xdata, ydata, ft, opts );
    plot( fitresult2, xdata, ydata );
    grid on
    xlabel('H')
    ylabel('M')
    Ms = fitresult2.Ms
    a = fitresult2.A
    b = fitresult2.B
    k = 0
    set (handles.edit2,'String',num2str(a))
    set (handles.edit3,'String',num2str(b))
    set (handles.edit4,'String',num2str(k))
    set (handles.edit5,'String',num2str(Ms))
    
    
    

    

elseif (popvalue == 4)
    [xdata, ydata] = prepareCurveData(t1, t2);
    ft = fittype( 'Ms*(1-B/x^2)', 'independent', 'x', 'dependent', 'y' );
    opts = fitoptions( 'Method', 'NonlinearLeastSquares' );
    opts.Display = 'Off';
    [fitresult3, gof3] = fit( xdata, ydata, ft, opts );
    plot( fitresult3, xdata, ydata );
    grid on
    xlabel('H')
    ylabel('M')
    Ms = fitresult3.Ms
    a = 0
    b = fitresult3.B
    k = 0
    set (handles.edit2,'String',num2str(a))
    set (handles.edit3,'String',num2str(b))
    set (handles.edit4,'String',num2str(k))
    set (handles.edit5,'String',num2str(Ms))
end