[AC Question]

Devise = Note 7

[ManiacJoe]

What email app are you using?

If the email app lets you make that kind of change, it is probably done in the account settings, maybe in the "advanced" section.
If the email app does not let you do that, then you need to delete the account and add it again.

[Rukbat]

Most phone apps don't allow that - you have to go to the website for the email account and change it, then delete the address and add it back as POP3. (Remember, if you delete an email in a POP3 account, it's gone. POP3 is meant if you're using only one device to read emails.)