Solution

Check if the account is managed or unmanaged

1. Go to id.atlassian.com/manage-profile/email.
2. If the account is managed, you will see pop-up informing "   Managed account" :

For unmanaged accounts: 

The email address associated with the account can be changed by the user at any time:

1. Go to id.atlassian.com/manage-profile/email.
2. Enter the new email address.
3. Save changes.
4. Check the inbox of the new email address to find the verification message.
5. Click Verify your email and follow the instructions to conclude the update.

If an unmanaged user  has  used their new email address with an Atlassian cloud product or website:

If the email address you enter is already used in Atlassian you will get a notification:

To fix the issue, follow the steps below:

1. Login to the account associated to the desired email address and change its email address to another one (a third email address).
   1. The desired email address must be released from the existing Atlassian account so that it is available to be used on the original account.
   2. This other email address must be something accessible: either a personal account or an email alias
2. You will receive an email from Atlassian in your mailbox.
   1. Conclude the email verification and update on this other email address - doing so will fully release the desired email address.
3. Log back into the original Atlassian account and change its email address to the (now available) desired email address
4. A verification email will be sent to the new email address; complete the verification step to complete the email update

For Managed Accounts:

If you use a managed account, you won't be able to directly update your account's email address. Please reach out to your organization admins, only they will be able to update your account's email address.

A Managed account is a User who is being managed by an Atlassian organization due to Domain Verification. 

As an Organization Admin, if the user's new email address has not been used:

In Admin Hub (admin.atlassian.com),  click on Directory in the top bar > select Managed accounts > locate the user's Atlassian account and click into the fields to edit the values:

If you want to update the email address of a managed account to another email address, make sure you’ve verified the domain for the email you want to update to.

From the Email address field, enter the updated email address and click the checkmark. 

You can only update an email address if the new email address also belongs to a domain you verify for your organization. Changes made in the Admin Hub will propagate and update all instances where the User's Atlassian account is used. 

If you’re unable to verify the domain, let the user know they can create a new Atlassian account with that email address.

As an Organization Admin, if a User's new/desired email address has been associated to a new/duplicate Atlassian account and both Atlassian accounts are managed within the SAME Atlassian Organization:

1. In Admin Hub (admin.atlassian.com), navigate to your Atlassian Organization's Managed accounts page, locate the new/duplicate Atlassian account with the DESIRED Email Address and change that account's Email Address to something else (eg user-invalid@domain.com)
   1. This temp/proxy email address must be within your verified domains
   2. This will release the DESIRED email address so that it can be used on a different Atlassian account
2. Locate the User's Original Atlassian account and change its Email Address from OLD Email Address to DESIRED Email Address
   
   1. After updating the User's Original Atlassian account to the DESIRED email, you can delete or deactivate the new/duplicate Atlassian account

If a User needs to change the Email Address of their Unmanaged Account to a New Email Address that's Managed by an Atlassian Organization and associated to a New/Duplicate Atlassian Account:

1. In Admin Hub (admin.atlassian.com), navigate to your Atlassian Organization's Managed Accounts page, locate the New/Duplicate Atlassian account with the DESIRED Email Address and change that account's Email Address to something else (eg user-invalid@domain.com)
   1. This Temp/Proxy Email Address must be within your Verified Domains
   2. This will release the DESIRED Email Address so that it can be used on a different Atlassian account
2. Have the User login to ID.atlassian.com with OLD/Original Email Address, navigate to https://id.atlassian.com/manage-profile/email and change their Email Address from OLD Email Address to DESIRED Email Address
3. A verification email will be sent to the DESIRED Email Address; clicking on the link will open a new window where the User will need to input the Atlassian Password associated with the Old Account to complete the change

Notes to Organization Admins:

• If your Organization is utilizing Atlassian Access with Single Sign-on, presuming that your Managed Users have logged in via at least once with their Old Email Address, changes to your User's Email Addresses first need to be made within your Identity Provider so that when the User logs into Atlassian with their New Email Address, their Atlassian account will be Just-in-Time Updated with the New Email Address 
  • If the User's Original Atlassian account is not linked with your IdP (eg they did not login at least once via with their Old Email Address) a New/Duplicate Atlassian account will be created with the User's New/DESIRED Email Address; follow the above steps for if a User's New/Desired Email Address has been associated to a New/Duplicate Atlassian Account and both Atlassian accounts are managed within the SAME Atlassian Organization