all messages from my att.net are gone !

This has just happened to me also. And AT&T needs to fix it asap! My emails still show on my laptop but my phone no longer displays them!
I have an LG g2 and must have a robust email on my phone.
Question? There used to be a setting on my email phone to display up to 100 messages. This option is now gone.
This could cause me to drop Att as my provider.
Can tech please respond?

MV, You might check your emails again. Today mine all showed up back in my phone inbox.
Some things I tried... Deleting my email acct and then adding it back. Forced syncing so that the servers would communicate. And I also 'showed all folders' and then went into several which forces syncing in the separate folders as well. Good luck.

MV,
Here's something else that could work. My own emails all disappeared again this week. I was using the email app that came with my phone. (An Android.) I loaded and installed the free AT&T email app from Google Play, deleted the pre-installed app, and instantly all my emails were restored. This same process should work with an iPhone, through the Apple Store. Try that and see if it works.