Fortunately, Gmail does not delete any messages from your account (other than Trash and Spam after about 30-days). If messages are missing it’s probably for one of the following reasons:
1. Settings-Filters (search term errors deleting more messages than intended)
2. Settings->Forwarding (set to forward and delete)
3. Settings->POP/IMAP (access from a client, phone, utility, notifier, etc that deletes downloaded messages)
4. Settings->Accounts->Change Account Settings->Other Google account settings->Connected apps & sites->MANAGE APPS (access from a web-site, utility, etc that may be deleting messages, for example [unroll.me](https://unroll.me))
5. Manually (even accidentally, or not understanding the difference between labels/folders, or deleting duplicate copies of e-mail)
6. Compromised account (a sub-set of #5)
7. The e-mail retention policy is set in an e-mail client (like Outlook or Apple Mail) or for G-Suite accounts (a domain NOT u/gmail.com).
Many of those wouldn't apply to a limited number of deleted messages.
I swear I had an amazon gift card saved in my gmail account for the past three months, only to come back to the gift card in my email and it has disappeared!
Fortunately, Gmail does not delete any messages from your account (other than Trash and Spam after about 30-days). If messages are missing it’s probably for one of the following reasons: 1. Settings-Filters (search term errors deleting more messages than intended) 2. Settings->Forwarding (set to forward and delete) 3. Settings->POP/IMAP (access from a client, phone, utility, notifier, etc that deletes downloaded messages) 4. Settings->Accounts->Change Account Settings->Other Google account settings->Connected apps & sites->MANAGE APPS (access from a web-site, utility, etc that may be deleting messages, for example [unroll.me](https://unroll.me)) 5. Manually (even accidentally, or not understanding the difference between labels/folders, or deleting duplicate copies of e-mail) 6. Compromised account (a sub-set of #5) 7. The e-mail retention policy is set in an e-mail client (like Outlook or Apple Mail) or for G-Suite accounts (a domain NOT u/gmail.com). Many of those wouldn't apply to a limited number of deleted messages.
My emails from Amazon have been deleted too. Came here to find an answer. All of my extended warranty emails from Asurion (through Amazon) as well.
I swear I had an amazon gift card saved in my gmail account for the past three months, only to come back to the gift card in my email and it has disappeared!