Happened all the time to me. I would just grudgingly enter everything in again, and after about two attempts it would finally let me through.

No idea why their damn login page is always so horribly buggy.

Oh, and the EBT page is even worse! I still haven’t been able to get anyone to help me with password recovery because they just keep referring me back to the same page that refuses to allow me to change my password, rejects all new passwords as “already used earlier” (when they are literally randomly generated and it’s therefore impossible for me to have already used them), and then locks me out permanently.