Where is my past email data?
Where is my past email data?
Why my inbox is empty?
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If an account is unused or dormant for 12 months, it is deactivated and its emails are deleted, more info here: https://help.yahoo.com/kb/SLN2018.html
If this does not apply to you, You can try doing a search or doing an email restore if the email was deleted in the past 7 days.
help.yahoo.com/kb/SLN2552.html
In case you are using a mail client such as Outlook or the Native mobile app, emails may be deleted by that third party client. We do recommend accessing your mail via http://yahoo.com or the Yahoo Mail app to avoid this issue.