Form Emails: Why notification/auto-responder is not sending?

I'm having the same problem... no notifications and no auto response 

I've checked your account email history and I  can see  emails are showing as sent, you may also check it on your end by following this guide: How-to-View-All-Your-Form-Email-History

So far, we're experiencing an issue with our emails, our developers are aware and working on this, currently emails should be delayed, but they should be sending normally as soon as possible.