I can't send emails says username or passcode incorrect, what should I do?

[iMore Question]

can't send emails says username or passcode incorrect

after iphone 9.1 update,

 

[Rob Phillips]

can't send emails says username or passcode incorrect

Welcome to iMore! Go to Settings > Mail, Contacts, Calendars and delete the email account by tapping on it and then tapping on "delete account". Then add it back in.