diff --git a/src/gui_qt/main/management.py b/src/gui_qt/main/management.py
index b9c6f4a..86d1b41 100644
--- a/src/gui_qt/main/management.py
+++ b/src/gui_qt/main/management.py
@@ -434,7 +434,7 @@ class UpperManagement(QtCore.QObject):
         models = {}
         fit_limits = fit_options['limits']
         fit_mode = fit_options['fit_mode']
-        we = fit_options['we']
+        we_option = fit_options['we']
 
         for model_id, model_p in parameter.items():
             m = Model(model_p['func'])
@@ -453,8 +453,10 @@ class UpperManagement(QtCore.QObject):
                 data_i = self.data[set_id]
                 set_params = model_p['parameter'][set_id]
 
-                if we.lower() == 'deltay':
+                if we_option.lower() == 'deltay':
                     we = data_i.y_err**2
+                else:
+                    we = we_option
 
                 if m_complex is None or m_complex == 1:
                     _y = data_i.y.real