Fatal error on Activating LearnPress plugin

Hi,

I installed the core LearnPress plugin and upon Activation, it caused a Fatal error and I can no longer access wp-admin.

I have a backup so can revert to a saved version but would like to continue with LearnPress if possible.

Fatal error: Uncaught Error: Call to undefined function wp_get_current_user() in /home/zonev926/public_html/abundant-living-oils.com/wp-includes/capabilities.php:640 Stack trace: #0 /home/zonev926/public_html/abundant-living-oils.com/wp-content/plugins/learnpress/inc/admin/lp-admin-actions.php(19): current_user_can(‘manage_options’) #1 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/class-wp-hook.php(286): _learn_press_set_user_items(Object(WP_Query)) #2 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array) #3 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/plugin.php(531): WP_Hook->do_action(Array) #4 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/class-wp-query.php(1753): do_action_ref_array(‘pre_get_posts’, Array) #5 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/class-wp-query.php(3404): WP_Query->get_posts() #6 /home/zonev926/public_html/abundant-living-oils.com/wp-includes/post.php( in /home/zonev926/public_html/abundant-living-oils.com/wp-includes/capabilities.php on line 640
The site is experiencing technical difficulties. Please check your site admin email inbox for instructions.

The page I need help with: [log in to see the link]