Ignite: Fatal Error, Cannot call overload function in class-wp.php line 529

Hi there.
I am using Ignite, not Ignite Plus. When I save sometimes (not every time) or when I try to navigate around my website, I get the following error and I have to reload the page or back up and try it again, or whatever. It resolves but it’s unprofessional for my website to be doing this to users. Here is the error:

Fatal error: Cannot call overloaded function for non-object in /home/shawndady/public/artemiscopywriting/wp-includes/class-wp.php on line 529

I looked in cPanel’s File Manager at the code and here it is below. I don’t want to mess with it, but why would this be happening? Can I fix anything myself?
Thanks,
Shawn Dady

This is the code is class-wp/php. Line 529 is wp_get_current_user();
/**
* Set up the current user.
*
* @since 2.0.0
*/
public function init() {
wp_get_current_user();
}