Why did this happen and how can I get them all back. I have not found the “Sync” area where I can select never delete any messages or something like that. These emails are very important to me.
iPad Pro 12.9-inch Wi-Fi, Cellular
Mail is unlikely to disappear from your device unless you have configured automatic deletion of read-messages:
Settings > Mail > Accounts > [your email account] > [account] > Advanced > Deleted Messages
You might wish to verify that the email remains accessible in your email providers servers. Try logging-in to your webmail service from a web browser to verify that the email is still present in your account.
If you discover that your email is not visible via webmail, you’ll need to check with your mail provider for deleted mail recovery - as otherwise your lost/deleted email messages will not be recoverable.
Mail is unlikely to disappear from your device unless you have configured automatic deletion of read-messages:
Settings > Mail > Accounts > [your email account] > [account] > Advanced > Deleted Messages
You might wish to verify that the email remains accessible in your email providers servers. Try logging-in to your webmail service from a web browser to verify that the email is still present in your account.
If you discover that your email is not visible via webmail, you’ll need to check with your mail provider for deleted mail recovery - as otherwise your lost/deleted email messages will not be recoverable.
Emails on my iPad Pro are disappearing
