Thanks for replying, John. I have tried, but it didn't seem to fix the error completely. I took your suggestion and reduced the step size to 0.01, but now TOPAS keeps refining without doing anything to the calculated plot. It stays flat while RWP goes down to 34 and stops
I am enclosing the data file and code. I would appreciate it if you could comment.
------_Code-------
continue_after_convergence 'Comment out to stop
r_p    74.2758777	r_p_dash    92.9476929
r_wp   33.8144986	r_wp_dash   80.699339
r_exp  0.719803335	r_exp_dash  1.71783276
gof    46.9774131
weighted_Durbin_Watson   0.21349848
'do_errors
'-----------------[SK200_70Ge]-----------------------
xdd MOTR_AADN_01_0002.h5.2th_BKGD_SUBTRACTED.xye 'File name with extension
	
r_exp  0.719803335 r_exp_dash  1.71783276
r_wp  33.8144986 r_wp_dash  80.699339
r_p  74.2758777 r_p_dash  92.9476929
weighted_Durbin_Watson  0.21349848 gof  46.9774131
 
start_X  1.5   
finish_X  13.53 
x_calculation_step 0.01
bkg @  309.023647`  159.619286` 0 0
str
	r_bragg  76.2881301
	phase_MAC  0.942220333
	phase_name "Cr2Ga(0.3)Ge(0.7)C"
	MVW ( 167.551, 45.729`, 15.778`)
	space_group 194
	scale  @  1.40775053e-005`
	
	Phase_Density_g_on_cm3( 6.08421`)
	
	Hexagonal ( @  2.233438`,@  10.585572`)
	site Cr num_posns  2 x =1/3; y =2/3; z =0.586 occ Cr 1 beq =1
	site Ge num_posns 2 x =1/3; y =2/3; z =1/4; occ Ge !a 0.7 beq !b 1 occ Ga =1-a; :  0.30000 beq =b; :  1.00000
	site C num_posns  2 x  0 y  0 z  0 occ C  1 beq  1
Create_2Th_Ip_file(2Th_Cr2Ga(0.3)Ge(0.7)C.txt)		
'--------------------------------------
	str
		r_bragg  81.0244325
		phase_MAC  0.163790491
		phase_name "C"
		MVW ( 72.064, 32.430, 46.788)
		space_group R-3mh
		scale @  0.000136866085`
		
	Phase_Density_g_on_cm3( 3.68996`)
	
	Trigonal( @  1.933574`, @  10.016008`)
	site C num_posns  6 x  0 y  0 z  0.16667 occ C  1 beq  1
Create_2Th_Ip_file(C.txt)
'--------------------------------------
	str
		r_bragg  74.0900105
		phase_MAC  0.725902558
		phase_name "Cr3Ge"
		MVW ( 457.257, 80.030, 37.434)
		space_group Pm-3n
		scale  @  6.99326466e-006`
		
	Phase_Density_g_on_cm3( 9.48757`)
	
	Cubic(@  4.309413`)
	site Cr num_posns  6 x =1/4; y  0 z =1/2; occ Cr  1 beq  1
	site Ge num_posns  2 x  0 y  0 z  0 occ Ge  1 beq  1
Create_2Th_Ip_file(Cr3Ge.txt)
'------------------[Output-Graphical_Data]--------------------
Out_Yobs_Ycalc_and_Difference(SK200_70Ge_Graphical_Data.txt)
'--------------------------------------
for xdds   
	{  
      ' Enter INP text    
      macro x_offset_eqtn_1 {a_coef_1((Rad 2Th)2) + b_coef_1((Rad 2Th)) +  c_coef_1}          
         prm a_coef_1 -0.00001'  9.5598462e-06 '- 
         prm b_coef_1  0.00008 ' -0.000101340104 ' 
         prm c_coef_1  0
  
          
     GeometricIntensityFactorFlat2DDetector     
     ReflectionProbability     
     LorentzCorrection     
     th2_offset = x_offset_eqtn_1;   
   
    User_Defined_Dependence_Convolution(gauss_fwhm, , @, 0.00010`)   
    User_Defined_Dependence_Convolution(lor_fwhm,  , @, 1.53883`)   
    User_Defined_Dependence_Convolution(gauss_fwhm,  Tan(Th)    , @, 87.20613`)  
    User_Defined_Dependence_Convolution(lor_fwhm,  Tan(Th)    , @, 0.00191`) 
 lam   
    ymin_on_ymax  1e-06   
    la  1 lo !WavelengthID31 0.16531226319520955 min =0.164; max =0.167; lh  0.001   
	  
 convolution_step 4   
}	  
'----------------[MACROS]----------------------
   
   macro vals_after_converg { val_on_continue = Val + Rand(-0.06Val, 0.06Val) } 'Simple macro used with the continue_after_convergence keyword above
         
   
   macro GeometricIntensityFactorFlat2DDetector       
      {       
      'This includes the cosine dependance for longer transition through detecting layer (Cos(2Th) at higher angles       
         scale_pks = 1 / Cos(2 Th);       
      }       
   macro ReflectionProbability      
   {      
      ' the probability of a reflection being in a scattering position. Usually bundled with the Lorentz correction      
      scale_pks = 1 / Sin(Th);      
   }      
   macro LorentzCorrection      
   {      
      ' not sure this is perfectly correct for a 2D detector. Correction for the path taken through the Ewald sphere during the rotation of the crystallite in the primary beam      
      scale_pks = 1 / Sin(2 Th);       
   }