If you see the message
“You have set your browser to not allow third party cookies”
on a login page, it does not indicate that there is an issue with your web page’s login and instead means that YOUR browsing settings need to be updated to allow third party cookies.
Third-party cookies allow a member to login and stay logged in to a third-party login system for the duration of their browsing session. Any website that offers login uses third-party cookies to keep the visitor logged in, as third-party cookies is currently the only available methodology to keep someone logged in. Without third-party cookies being enabled, login functionality would not work.
Information on how to reset your cookie permissions can be found here How to reset your third-party cookies.