The code it is not showing in the list but I added my sender

I added my sender email and verified it with the code however I did not hit save (as we don't have to save anywhere else I assumed it was auto saving)

Now I've got back in and the new verified email isn't showing in the drop down list and when I try to add it again it says it's already been verified.

Is there anything else I can try to get the email back? Thanks :)

This is a re-post of a comment on How to Add a Custom Sender Address to an Email Alert