tested

rowers/models.py

@@ -1216,7 +1216,7 @@ class Rower(models.Model):
     polartokenexpirydate = models.DateTimeField(blank=True, null=True)
     polarrefreshtoken = models.CharField(default='', max_length=1000,
                                          blank=True, null=True)
-    polaruserid = models.IntegerField(default=0)
+    polaruserid = models.IntegerField(default=0, blank=True, null=True)
     polar_auto_import = models.BooleanField(default=False)
 
     garmintoken = models.CharField(

rowers/views/teamviews.py

@@ -571,7 +571,7 @@ def invitation_reject_view(request, id=0):
 def rower_invitations_view(request, code=None, message='', successmessage=''):
     if code:
         teams.remove_expired_invites()
-
+        
         res, text = teams.process_invite_code(request.user, code)
         if res:  # pragma: no cover
             messages.info(request, text)