For Wordpress sites, chat administrators can control if they want to give access of chat to Guest/Unregistered users also or just the logged-in users.
To do so, please go to iFlyChat settings page in Wordpress Admin Panel. Then click on App Settings option.
To allow guest users to chat, set the option "Allow Guest Users" as "Yes"; as shown in the image below.
To allow only logged-in users to chat, set the option "Allow Guest Users" to "No".