diff --git a/src/postorius/forms.py b/src/postorius/forms.py
index fad4875..4f84c5c 100644
--- a/src/postorius/forms.py
+++ b/src/postorius/forms.py
@@ -600,7 +600,7 @@
     )
     if __version__ < '1.9':
         subject_prefix = forms.CharField(
-        label=_('Subject prefix'),
+            label=_('Subject prefix'),
         )
     else:
         subject_prefix = forms.CharField(