Are you referring to the plugin Firebar or Popup Fire? In your post you mentioned Firebar, but this topic in under the Popup Fire Forum.
It seems strange that you are unable to change the text color settings and that it is not displaying on your site. Can you please set up a test page for us and display the Firebar only on that page so we can have a look at what could be going wrong. Make sure to include a link to this page so we can reference it.
To speed up this process you can share your WordPress login credentials with us so we can have a look at you settings to see if everything is ok. If you do share your login credentials with us please make sure to mark the reply as private.