fix bug

Author: ldm0206

merge.py

@@ -206,8 +206,9 @@ async def main():
                     for display_name_node in display_names:
                         display_name = display_name_node[0]
                         all_channels_map[display_name] = map_id
-                elif len(all_programmes[map_id]) < len(programmes[channel_id]):
-                    all_programmes[map_id] = programmes[channel_id]
+                else:
+                    if len(all_programmes[map_id]) < len(programmes[channel_id]):
+                        all_programmes[map_id] = programmes[channel_id]
                     for display_name_node in display_names:
                         display_name = display_name_node[0]
                         if display_name not in all_channels_map: