I hope you are well today and thank you for your question.
Could you please try clearing and temporarily deactivating the W3 Total Cache that you are using on your website?
Also, this can be due to plugin conflict on your site so please try temporarily deactivating all plugins except Unyson plugin and WpBakery page builder plugins and see whether everything works fine and then enable the plugins one by one to see which plugin is conflicting if any.