Follow these instructions to restore a previous version of a page on WordPress.
1. Make sure Revisions is checked in your Screen Options (drop down at top right of page):
2. The Revisions box will appear below Yoast SEO box with dates/times of all revisions made on that page:
Alternatively, to pull up the Compare Revisions window, you can select Revisions from the Publish box (top right of page):
3. In the Compare Revisions window, select the version you want to go back to. The most recent version appears on the right, with the changes highlighted.
You can also use the slider to choose which version you wish to restore.
4. Click Restore This Revision button.
5. Click Update, and the page will be restored.