To change the login email for a Moralis developer account, contact Moralis support from the email currently associated with that account. If you no longer have access to it, explain that in your request so support can advise on account verification.
The billing email is a separate setting. If you only need to update billing email, sign in and open Settings → Account, then choose Edit Billing Email.
Do not share your password, two-factor authentication codes, or wallet seed phrase with support.