Online portal not linking account (Blank screen)

The online portal does not allow me to link an account as it only gives you a blank screen. There is no online support or self help options for this and for that reason nobody is able to assist.

Tried interacting with the physical stores and they advise that only the contact centre can assist and the email service is equally as useless because they only tell you to refresh your page. Nothing works for numerous days. And there’s no way of maintaining your information on the portal they direct you to.