1)On the Cases object page layout, I've added the related list Activity History.
2)In the page layout, I've opened the wrench on the related list and made sure the buttons for 'Log a Call' and 'Email' are checked.
3)In the page layout, I've added the buttons to the page layout for lightning.
4)'Log a call' and 'Email' are configured in Global Settings and these buttons appear on other object's related lists.
5)While editing the Cases page, I'm using Related List-Single in Tabs and the buttons 'Log a Call' and 'Email' are missing.