I'm confused!
What are the 'messages' you refer to? They don't appear to be posts to The Answerbank, as your profile shows no relevant activity (unless you're referring to the 'Merkel' post).
So I'm assuming that you're referring to emails being sent from the wrong account. If you (and your husband) use a web-based email system, where you access your mail through a website (which you view in your browser) then simply clicking on 'Log Out', and then logging in again with his own account details, should fix the problem. (If it doesn't, clearing the cookies and cache from his browser will definitely do so).
If you use a 'proper' email client (such as Outlook Express, Outlook, Windows Live Mail, Windows 10 Mail or Thunderbird) to access your email mail, you need to check that you've got two separate accounts configured. If so, one of them will be set as the 'default' account and, unless you change it, outgoing mail will always be sent via that account. (To change the account that's used, simply click in the 'From' field and select from the list offered).