Fix issue

tournaments/models/tournament.py

@@ -733,12 +733,17 @@ class Tournament(models.Model):
 
         # all started matches have ended, possibly
         last_finished_match = self.last_finished_match()
-        if last_finished_match and last_finished_match.round:
+
+        round = last_finished_match.round
+        if round is None: # when the last finished match is in the group stage
+            round = self.round_set.filter(parent__isnull=True).order_by('-index').first()
+
+        if round:
             # print(f'last_finished_match = {last_finished_match.name}')
-            round_root_index = last_finished_match.round.root_round().index
+            round_root_index = round.root_round().index
             # print(f'round_index = {round_root_index}')
             if round_root_index == 0:
-                return last_finished_match.round
+                return round
             else:
                 round = self.round_set.filter(parent=None,index=round_root_index-1).first()
                 if round: