Hello GaTxLady,
Welcome to Apple Support Communities. It sounds like you're having trouble with Mail on your iPhone. I'd be happy to share information that may help.
First, be sure your device is fully updated: Update your iPhone, iPad, or iPod touch. (Be sure to have a current backup prior to updating.)
If that does not resolve the issue, navigate to Settings > Passwords & Accounts > tap on the account > Delete Account.
Then, restart your iPhone: Restart your iPhone.
Finally, add the account again: Add an email account to your iPhone, iPad, or iPod touch.
Take care.