The Captcha continues on iPhone, iPad and laptop. I share Jage's suspicion of Tapatalk, esp. Given my recent experience with ads popping up in the unread threads section on this forum but not others. If it's challenged the forum's security settings in some way, it may not matter whether someone has used it themselves over not.
I share 86Scotty's despair about TT's recent "improvements" and will probably drop it. However, whether it's the culprit or not, fixing this login bug may be very difficult.
FWIW, I'd encourage anyone with this error to change their password and make it very secure, at least for a while. That means at least 8 characters long with a mixture of uppercase, lowercase, numbers and punctuation marks. Here's a website that can make one for you: https://identitysafe.norton.com/password-generator#
. Another approach that I like is to write the first words of a song you like and use their first letters for a password. Change some vowels to numbers (a=1, etc.), capitalize something, throw in a question mark or semi-colon and you're done. Write it down, though.