I tried to report this through the Chatbot, but got no response there.
Long story short, the password change function in the web app will accept passwords that the login form does not accept. ie, it's possible to set your password to something that cannot actually be used to log in, which then forces a password reset to access the account. It's really annoying when you run into it.
The following two passwords were accepted for changing my password, but not for logging in: