old email is not valid but can’t delete it

I want to change ( delete) an old email in my security settings. The company is out of business. My phone number and other email addresses are listed but when I try to change it , I get a message that wants to send a code to the old email account. It won't let me send the code to anything else. Please  help. Also when I post here, my husbands name comes up but I logged in with my hotmail address.