Responses bounces to notification email

I changed the notification email on a form we’ve used for years and now the responses filled in on the form don’t go out and are showing as “bounced”, the syntax for the email is right and other emails that go to that email work. Any thoughts, it seems that it’s just from the filled out form that is not going out.

I recommend opening a support ticket for this issue: I don’t think it’s something the community can help with efficiently:

Thank you.