recover email

I was emailing a unscrupulous car dealership about a car purchase. They made a statement in one of their emails that was evidence that they cheat their customers. Weeks later when I looked for the email to report them to the Better Business Bureau, the incrimnating email was gone. Can someone...

Absolutely panicking and freaking out right now. My iPhone X deleted 100s of thousands of emails from my accounts and they cannot be restored. I set it up from an iCloud Backup and it did NOT retain my email settings like it should so it was set to delete Trash emails after a week even though on...