I have a 404 error on all my pages! What do I do?

Try to reset your permalink structure. In your WordPress Dashboard go to Settings > Permalinks. All custom post types require additional slugs like /portfolio-item/, /destination-item/, /tour-item/, /property-item/, /listing/ etc. So you probably made a typo in your custom structure. Select an alternative permalinks structure -> Save Changes. Change it back to your standard structure and hit Save Changes once again.
If you’re still getting a “404 Page Not Found” error, try other remaining methods.

permalink slug