Our wifi login requires the use of the DNS protocol. If a member's computer is using a custom DNS server instead of the Pfsense routers, the login won't work. Try to disable any custom DNS settings on the device.
Another source of problems could be from people trying to go to a page using https. In order to be redirected to the login form, people should visit a site that uses only http, for example, http://google.com.
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