Check the Yahoo Mail Trash folder
Check the Yahoo Mail Spam folder
Use Yahoo Mail search to find the missing email
Restore the email from Trash if it is still there
Recover deleted emails from Yahoo if they were deleted within the last 7 days
Submit a Yahoo Mail restore request through Yahoo Help
Sign in to the correct Yahoo account
Check all connected devices for synced copies of the email
Review any email forwarding or backup settings
Contact Yahoo Support if the email cannot be restored