Have you tried refreshing permalinks? Or does the site have cache plugins installed? If so, clean them. Below is information on how you can refresh direct links: Step 1: In the WordPress admin area, go to “Settings > Permalinks” Step 2: Click “Save Changes” Step 3: Permalinks and rewrite rules are flushed.
Both from the My Account tab and from the email sent to the client, it is possible to download files such as zip, rar, etc. I also checked it now and it works. Please provide more details if the problem persists.