#Inbox app not working series
Newer versions of Mail app automatically retrieve the next series of email from your server each time you hit the bottom.
So, if you or a service like SaneBox copies a large number of older emails into your Inbox right now, you may only see those and brand new emails that arrived after the copy. The Mail app is showing you the emails that got moved into your Inbox most “recently” instead of your “newest” emails. You can in fact access the more recent items (via your web mail or even an alternate email app or email client.) The Mail app is actually grabbing the wrong subset of your Inbox email which causes some email to appear to be missing.
IPhone: iOS Mail app not displaying all my latest email in Inbox