Error: "Please enable cookies"

I am using Brave on iOS. It’s the latest version of Brave and of iOS. When I go to one particular internal web site and it displays the login I have a chance to “save the password”. However when I try and click that box I get an error that I should enable cookies. I have turned off ever setting that relates to security and cookies in Brave and I am still receiving the error.

Unfortunately this is an internal web site which you won’t be able to access as a test. Can you give me any general idea of what might be causing this? Or specifically all the settings that I might have to change in Brave to convince this screen that it can save cookies?