Hi,

I can use Elementor Pro version with the theme without any issue.

Have you tried to deactivate all plugins and check it again? If not yet, let's do that. Please try to deactivate all plugins ( except plugins come from the theme & Elementor & Elementor Pro ) and try it again. If it works, let's enable each plugin to check what's plugin caused this issue. 

Best Regards,

PenciDesign