How to make tokens display correctly?
The token used to get the user who wrote the content is not [user:name]. This is the username of a user account that you are trying to view, so this might not be available on the node page as we are not referring a user. 

To display the author name you should use [node:author:name].

If you install the token module you could go to the Help > Token (admin/help/token) page and see the available tokens. 

For more details and a list of the available tokens, see this page.

EDITED As per suggestion in comment.