$540 via promo credit when you add a new smartphone line with your own 4G/5G smartphone on postpaid Unlimited Plus plan between 5/18/23 - 5/31/23 & port-in req'd. Promo credit applied over 36 months; promo credits end if eligibility requirements are no longer met.
Verizon doesn't automatically delete messages from your inbox.
Any time mail disappears from the server, there's a pretty good chance there's some device pulling it off. This can happen even without you intending it to. For example, the default Verizon setup for a long time (and possibly still) configured Outlook automatically unless you were paying attention and unchecked the box during the install.
The easiest way to fix it is to change your password. Once the device(s) can no longer authenticate, the disappearances should stop.