There is a quirk in how that system works. If you are requiring email verification, when you change the email address in one of the profile edit pages as a user, it does not 'update' persay in the field, but the database is updated and a notification is triggered. The user must validate the new email before it will appear in their user profile.
Please verify that you are using notifications and email verifications, and that email services are working.
Then - if you have 'two' fields that display the email address - try to change one - save and check for notification of verification. If no notification, attempt change on other email address field - one should throw notification and will then set the change once it's validated.
I ran into this in older versions and did not know if it was still an issue.
Language should be added to the postback that displays message to user upon change attempt to check mail or cause page reload if no verification needed.
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