It's common to have to remove your email account to address login issues and other email issues, such as being unable to receive or send emails using the iPhone X mail app. Here's how you do it:

1. Go to the Home screen and select Settings from the drop-down menu.
2. Select Accounts & Passwords from the drop-down menu.
3. To remove an email account, go to the Accounts area and touch on it.
4. To delete an account, tap Delete Account.
5. To confirm account deletion, hit Delete from My iPhone when prompted.
6. so now the email account is deleted

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