First, you should check that you have remembered to press the send invite button for that Collaborator. If the “Invite Status” shows an empty circle, then you need to press the send invite button.
If your trading partner is having difficulties setting a password, please instruct them to use the forgot password link https://apps.enable.com/forgot-password. Only the most recent forgotten password link will work, so make sure your trading partner is using the most recent link.
If you are unable to resolve the issue with your trading partner and they are still experiencing a technical issue, please instruct them to: