Why Combobox cascade doesn't work

Why does the cascade Combobox no longer work? I don’t understand the change in the survey solution anymore. Every time you download, it’s an attachment error, or before it didn’t.
Please need a survey solution to review the Combobox cascade issue

With the new changes select questions support attachments in categories. A new optional column appeared that could be set during categories update. Please check the files you are uploading.