I'm guessing that someone's written a script to brute force submit all legal names, or there's a bug. I started with London, ran up against the character limit, then went to https://en.wikipedia.org/wiki/List_of_national_capitals and selected Dili, the capital of East Timor.

Every combination of random characters I substitute for the 8 and tilde in "dilI~8 e 8~Ilid" always produces "Sorry, this password is already in use."

Eventually got to "Sorry, all of today's passwords have been used. You win, ..."