I have had the same experience. I called many years ago to have my primary email deleted because it was hacked, and the so-called representative kept my email and gave me a new one. Now I am limited on what I can do since it is not the primary email. Whenever I contact Cox, they tell me I have to delete my old email. I ask them why you can't do that on your end, and they always tell me they do not have that option. What the heck! This is so ridiculous; they have no problem taking my money but can't get rid of my old email that they failed to protect from viruses and being hacked!ðŸ˜
The username might have Cox.net in it and may be used to sign into Cox.com but it is no more related to Cox then the username/email you use to sign into Facebook with.
Also, Cox is responsible for maintaining their systems, but most "hacks" come in from the user side. Malware, scareware, exploits and data breaches of other systems. Try looking up the email here.
