Hi there, this is a bit complicated to explain but I'll try my best. I have a real estate site and trying to use the [wpv-post-author] to display the author of the property (want to do some css targeted to all the posts by a certain author).
My real estate theme is set up so that a custom template page made in visual composer with shortcodes is how all properties on the site display. Each agent/user is the author of a property, however the template page is made by the admin, so it gets a bit complicated when trying to show the property author.
When I enter this shortcode into the template page, it works perfectly and displays the correct agent/author:
However, as soon as I enter this in the template page (using the text tab for the WordPress page to wrap a div around a section of the template using the agent/author nickname as the class), it reverts to the template author, which is the admin, and won't display the agent/author name anymore:
I took this code and test it and the information was displayed correctly in both cases for me.
Taking a look at your plugins list I noticed that you have quite a number of them installed.
This is what could be causing your issue. What I recommend that you do is to temporarily disable all your non-toolset plugins and check again to see if the issue remains.