Ethereum addresses cannot be deleted as they are on the blockchain. We can, however, delete the personal data associated with your Argent account. Once this is deleted it cannot be reversed.
Please contact support@argent.xyz from your registered email address and let us know your Argent username if you would like this personal data deleted.
Personal data we hold can consist of: Email; Phone; Requested Argent username; Device and App version.
If you would instead just like to change your email or phone number you can from account switcher (ETH or zkSync icon on the top-left in your Assets tab) > Settings > Account Details