OJS stores author metadata and user metadata separately; this is because repeat authors may change their profiles over time, and this shouldn't change previously-published information. If you change the data that's part of an article's metadata, that won't affect the author's profile and vice versa. The Journal Manager can edit user profiles; try correcting the email address there.
Note that OJS requires each user profile to have a different email address, so if a user registers twice with two different emails and tries to change one email to the same address as the other account uses, they'll be denied. In this case I'd suggest using the Journal Manager's "Merge Accounts" feature to combine the two accounts into one.
Open Journal Systems Team
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