Hello,
We found that you are having CDN cache which could be the reason of such issue according to next article -> https://themeoo.com/how-to-fix-changes-not-visible-in-elementor-error/
We didn’t find any plugin which could allow us to disable CDN so it seems it is enabled on your server. Please, check the problem once you disable CDN caching.
Also, we would recommend you to increase next values you have in XStore Control Panel -> System info -> https://prnt.sc/uFpf1C6Sep9B
You should contact your hosting provider with such question.
https://www.8theme.com/topic/doesnt-save-changes-in-elementor-or-theme-options/#post-307854
You may contact Elementor support with the same question, maybe they met such problems already and could help you faster than we can.
Regards