Hi pamboc,
As I understand it you are unable to send messages and the ones you do have downloaded from the server aren't displaying the contents. I would first quit the Mail app:
iOS: Force an app to close
Double-click the Home button.
Swipe left or right until you have located the app you wish to close.
Swipe the app up to close it.
Then I would do these steps from the following article for further assistance:
Get help with Mail on iPhone, iPad, and iPod touch
- Make sure your settings are correct using Mail Settings Lookup.
- Restart your iOS device.
- Delete the affected email account from your device.
- Tap Settings > Mail, Contacts, Calendars.
- Tap the affected email account.
- Tap Delete Account.
- Add your account again.
Thank you for using Apple Support Communities.
All the very best,
Sterling