That's a good point, besides not following the documentation (or they weren't aware they were supposed to "suppress payment of principal amount). They UI "stop sign" prompt should show the # of on the confirmation machine. It should accurately summarize everything they are doing, not just a simple "yes/no" they've seen a bunch of times.

Just like in Hawaii when they sent the wrong cell phone warning of an incoming NK missile attack, it could easily have been prevented if there was a dialog which said "You're sending this 'prompt' as a live alert to millions of cellphones (yes/no)".

Software always assumes people are paying attention but for serious usecases like this (which can't be undone for example, or sending hundreds of millions) there should be a sanity check dialog with real information.