Hi there!
I’m sorry to hear that you’re having issues with the calendar display. I will try to help you find a solution.
There seems to be a conflict with z-index somewhere. To fix this in your case, you will want to set a higher z-index on your header section.
Go to edit your header template in Elementor > Templates.
Select the Elementor Section that wraps all your header content.
Open the section’s “advanced” tab, and set the z-index to 102.
Hope that helps! Let me know if you have any other questions.
Thanks,
Sky