At the moment we don't have a way to change the email address of an account or to transfer existing account data to new accounts.
What we can do is delete your current account and you can start a new account completely fresh - this means there won't be any record of your app progress (sessions you've done or previous journal entries).
If you have an existing app store subscription you'll be able to transfer this to your new account by going to the subscription page (from the new account) and tapping on "Restore Purchases".
Please start your new account and then message us with the account email you'd like deleting.