do you mean that you are unable to type in the portal name ?
Or the portal server addy ?
What happens when you try and type it in ?
Are you using the KB button ?
Are you using the gear button to enter the menus ?
And once done typing it, are you trying multiple buttons to exit ? I know these mags can be slow in response, but hitting the buttons more then needed will mess up the function and seems it will not fix itself untill you exit without saving or reboot.
when are you attempting to enter the donation info ? Before you get the server entered ?
Try exiting that server authentication first, then get the server info entered, then continue with authentication credentials.