Why do i keep getting empty emails with no sender

Try turning the email account off and on : Settings > Mail > Accounts , then tap the account on the right, slide Mail to 'off', exit settings and go back into the Mail app, and then go back to Settings and slide Mail back to 'on'

If that doesn't fix it try closing the Mail app via the iPad’s multitasking bar : Force an app to close on your iPhone, iPad, or iPod touch - Apple Support

Yea that usually fixes it until email starts doing it again. Can this be fixed?

I've had times the app needed to be killed twice to get it to working again, and then it can happen again after about a week, although occasional a day or even again that same day.

I'm not sure why they appear, so I don't know how to permanently stop it