If a Contact needs to change their login email address (e.g. they are no longer email@example.com), they will need to edit via their Profile.
While logged in, go to your Profile image at the top right of the Public Facing Page.
Select your TidyHQ Account details and the Profile to reflect the new email address.
The Contact should now be able to login with the new (correct) email address.
Note: Your Contact Email is the address TidyHQ Pty Ltd use to send you things like ticket and membership information - The TidyHQ Account address is used to login.