User defined equation does not show up in batch curve fitting window

#pragma rtGlobals=3     // Use modern global access method and strict wave access.
#include <WMBatchCurveFitIM>
 
Function FitMySpectrum(ww, xx) : FitFunc    //code for the fitting of spectrum
 
    WAVE ww    
    Variable xx
    Variable w1=0, w2=0, w3=0, w4=0, w5=0, w6=0, qq=0
    Variable T1=0.23, S1=0.064, T2=0.09, S2=0.12, x1=1.92, x2=2.17
                                         
         // local variable
    
    
    //CurveFitDialog/ These comments were created by the Curve Fitting dialog. Altering them will
    //CurveFitDialog/ make the function less convenient to work with in the Curve Fitting dialog.
    //CurveFitDialog/ Equation:
    //CurveFitDialog/ qq(xx) =  (A1*(exp(0.5*(S1/T1)^2-(xx-x1)/T1))*erfc(0.707*(S1/T1-(xx-x1)/S1)))+(A2*exp(0.5*(S1/T1)^2-(xx-x2)/T2)*erfc(0.707*(S2/T2)-(xx-x2)/S2))
    //CurveFitDialog/ End of Equation
    //CurveFitDialog/ Independent Variables 1
    //CurveFitDialog/ xx
    //CurveFitDialog/ S1 --> Set equal to 0.064
    //CurveFitDialog/ T1 --> Set equal to 0.23
    //CurveFitDialog/ S2 --> Set equal to 0.12
    //CurveFitDialog/ T2 --> Set equal to 0.09
    //CurveFitDialog/ x1 --> Set equal to 1.92
    //CurveFitDialog/ x2 --> Set equal to 2.17
    //CurveFitDialog/ Coefficients 2
    //CurveFitDialog/ ww[0] = A1
    //CurveFitDialog/ ww[1] = A2
    
    return (ww[0]*(exp(0.5*(S1/T1)^2-(xx-x1)/T1))*erfc(0.707*(S1/T1-(xx-x1)/S1)))+(ww[1]*exp(0.5*(S1/T1)^2-(xx-x2)/T2)*erfc(0.707*(S2/T2)-(xx-x2)/S2))
        
End
 
//Second code
<pre><code class="language-igor">
 
Function FitMySpectrum(ww, xx) : FitFunc    //code for the fitting of spectrum
 
    WAVE ww    
    Variable xx
    Variable w1=0, w2=0, w3=0, w4=0, w5=0, w6=0, qq=0
    Variable T1=0.23, S1=0.064, T2=0.09, S2=0.12, x1=1.92, x2=2.17
                                         
     //CurveFitDialog/ These comments were created by the Curve Fitting dialog. Altering them will
    //CurveFitDialog/ make the function less convenient to work with in the Curve Fitting dialog.
    //CurveFitDialog/ Equation:
    //CurveFitDialog/ qq(xx) =  (A1*(exp(0.5*(S1/T1)^2-(xx-x1)/T1))*erfc(0.707*(S1/T1-(xx-x1)/S1)))+(A2*exp(0.5*(S1/T1)^2-(xx-x2)/T2)*erfc(0.707*(S2/T2)-(xx-x2)/S2))
    //CurveFitDialog/ End of Equation
    //CurveFitDialog/ Independent Variables 1
    //CurveFitDialog/ xx
    //CurveFitDialog/ S1 
    //CurveFitDialog/ T1 
    //CurveFitDialog/ S2
    //CurveFitDialog/ T2
    //CurveFitDialog/ x1
    //CurveFitDialog/ x2
    //CurveFitDialog/ Coefficients 2
    //CurveFitDialog/ ww[0] = A1
    //CurveFitDialog/ ww[1] = A2
    
    
    // Body code
    w1 = exp(0.5*(S1/T1)^2-(xx-x1)/T1)   
    w2 = erfc(0.707*(S1/T1-(xx-x1)/S1))
    w3 = ww[0]
    w4 = exp(0.5*(S2/T2)^2-(xx-x2)/T2)   
    w5 = erfc(0.707*(S2/T2-(xx-x2)/S2))
    w6 = ww[1] 
    qq = w3*(w1*w2)+w6*(w4*w5)
    return qq
    
End