[AC Question]

It also says username & password incorrect, I have entered a new email address on google which it has accepted but when I email it still says failed server changed password

[B. Diddy]

Welcome to Android Central! Is the Email app giving you this error message, or is it coming from the system?

If you're using the stock Email app, try going to its settings and remove the email account in question. Then add it back, and see if it works.