iOS Mail app deleted everything in my Yahoo Mail Inbox. How can I recover it?
I have used Yahoo Mail for 20 years and loved that I can access it from any iPhone, iPad or PC and it's always there. Unfortunately, my world came crashing down last week when ALL the 50,000+ messages that had been accumulating in my Yahoo inbox disappeared suddenly when checking email on my iPhone 5 using iOS Mail app. I assumed it would correct itself, as occasionally the messages briefly disappear when loading new email messages, but the Inbox was EMPTY, and only new emails would appear from that point on. Incredibly, all the messages I had previously moved to separate folders (receipts, sent mail, specific topics that I categorized, etc) in my Yahoo Mail were still there in the folders untouched, but the uncategorized messages left in the Inbox vanished.
I tried every trick I knew to try to fix it: I closed the mail app, turned iPhone off then on. I held down Power button and Home button for soft reset. I logged all my devices out of My Yahoo Mail account, turned phone off and on and and logged back in but mail is still missing and 5 days later not coming back. I tried looking at my Yahoo Mail on my desktop PC using the Yahoo Mail main website interface but nothing but new messages were showing up in my Inbox. I looked in other folders, but they weren't there, except I did see some messages from the 3 days prior to the disappearance in the Trash. Some of those I know I put in the trash, but some I don't think I intentionally trashed, so I moved those I could back to Inbox. Any device I had used in the past that had email in the inbox also "disappears as it connects to the internet to update the contents.
I next chatted with the tech support folks at Yahoo Mail, and they said that unfortunately they have seen this happen before, where a third party app like iOS mail is used and accidentally deleted email from Yahoo's server through an IMAP connection, and because the Yahoo app or Yahoo website wasn't used to delete it, their restore files don't contain the missing email and they are unable to restore the missing emails. Only if the emails were deleted on their servers would the emails be available in their restore files. That is so frustrating. I feel like my house burned down and I've lost so many things that were always available to look up by searching my emails. Does anyone have any more ideas? Has anyone else had a similar experience? I'm not sure exactly how it happened, but maybe the "trash all" button was accidentally pressed, but I would assume one would need to "select all" first, right?
HELP! and thank you in advance
iPhone 5, iOS 9.3.1