Hi ​@Helpmeplease, welcome to Box Community! I'd be glad to help you with your concern.

Please note that an email address can only be linked to one Box account. If the email is already registered to an account, it cannot be added as a secondary email to another account unless it has been released.

As outlined in our Canceling Your Box Account guide:

Deletion will not happen immediately, please allow time for the system to process the request.

The email address used for the free account cannot be used in any Box account until 120 days after account deletion.

That's why the system still recognizes the email as being linked to an existing account.

 To use the same email with a different Box account, you’ll need to:

• Change the primary email to a different one.
• Set the original email as secondary.
• Then remove it.

This process will release the email, making it available for use in another Box account.
 

To proceed, the canceled account must first be reactivated. Please contact billing@box.com using the email linked to the canceled account and request assistance with reactivation.

️ Steps to Add or Remove an Email Address

To manage your email addresses, follow these steps:

1. Login to box.com and navigate to Account Settings > Login and Email Addresses. 
2. Click Add More Emails.
3. Enter a valid email address.
4. Click Save.

An email verification will be sent to the address you entered. Click the verification link in the email to confirm and add the alternate email to you account.

The email address that you just added will be added as a secondary email. To make a secondary email address your primary email address:

• Click Make Primary next to the email address you want as your primary email address.

Lastly, to free up your email:

1. Click Remove next to the email address you want to remove.
2. In the confirmation dialog box, click Okay.

If you need further assistance, feel free to reach out.