diff --git a/gui/qt/main_window.py b/gui/qt/main_window.py
index 5c77a7511..944ca4df9 100644
--- a/gui/qt/main_window.py
+++ b/gui/qt/main_window.py
@@ -1505,7 +1505,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             self.show_error('\n'.join([
                 _("This transaction requires a higher fee, or it will not be propagated by your current server"),
                 _("Try to raise your transaction fee, or use a server with a lower relay fee.")
-            ])
+            ]))
             return
 
         if preview: