Hi,
If you use an old version earlier. I think you should still use WP Backery Page Builder instead of Elementor.
Because if you use Elementor, it will cause display errors in addition to the frontend.
- If you want to use Elementor, you should create a test site and do the following steps:
1. Export database from current site.
2. Import it to test site
3. Remove page has been build from WP Backery Page Builder.
4. Remove WP Backery Page Builder plugin
5. Rebuild page with Elementor.
6. After completing the experiment on the test site, you can return to the main website and repeat from step 3
Note: You should backup the site before updating it.
Best regards,
tb.