What happened to spam? None in days. Some good mail goes there too.
Why is there no spam email? None in over a week. How can I be sure no good emails are going there when it doesn't come anymore?
Leo Bricker shared this idea
If you find emails in your Spam folder that don’t belong there, you’ll need to mark the messages as "not spam’. Here’s how: https://help.yahoo.com/kb/manage-spam-mailing-lists-yahoo-mail-sln28056.html
Also, sometimes a filter can cause emails to bypass your inbox and be sent to either the trash folder or a different folder. You may need to check any filters you’ve created to make sure your messages are correctly organized: https://help.yahoo.com/kb/filters-organize-yahoo-mail-sln28071.html