If you are using COX for email you should plan your switch to something else right away
For your own benefit, if you have an @cox.com email address signup for something else today. outlook.com, gmail.com, yahoo.com, whatever you like. Most likely you will not stay with Cox for the rest of your life and the minute you cancel your COX account you have 90 days until they delete your account.
You may as well make the transition to an email service you can keep for the rest of your life now. That way you have the time to keep monitoring your COX account for people that will keep emailing it. In some cases you will need access to your old email to make any changes to your shopping sites, social media sites, news sites, etc. If you don't have access to your COX email then you could lose access to your other accounts because you won't be able to verify an email change.
Save yourself the future headache and start transition to a free email service now before you are rushed and have only 90 days to complete that change.