Courses unavailable – critical error in popup-header

Hello,
My course was working fine; it’s been a few weeks since anyone tried to get in, but today someone did. They can get to the main course page, but anytime a lesson is clicked a “there has been a critical error on this website” error message pops up. It does the same thing when I try.

All plugins, themes, and wordpress itself are up to date.

The debug gives the following:

“Fatal error
: Uncaught Error: Call to a member function calculate_course_results() on bool in /home/tx3mg91uceg5/public_html/wp-content/plugins/learnpress/templates/single-course/content-item/popup-header.php:22 Stack trace: #0 /home/tx3mg91uceg5/public_html/wp-content/plugins/learnpress/inc/lp-template-functions.php(924): include() #1 /home/tx3mg91uceg5/public_html/wp-content/plugins/learnpress/inc/templates/class-lp-template-course.php(534): learn_press_get_template(‘single-course/c…’) #2 /home/tx3mg91uceg5/public_html/wp-includes/class-wp-hook.php(292): LP_Template_Course->popup_header(”) #3 /home/tx3mg91uceg5/public_html/wp-includes/class-wp-hook.php(316): WP_Hook->apply_filters(”, Array) #4 /home/tx3mg91uceg5/public_html/wp-includes/plugin.php(484): WP_Hook->do_action(Array) #5 /home/tx3mg91uceg5/public_html/wp-content/plugins/learnpress/templates/content-single-item.php(46): do_action(‘learn-press/sin…’) #6 /home/tx3mg91uceg5/public_html/wp-includes/template-loader.php(106): include(‘/home/tx3mg91uc…’) #7 /ho in
/home/tx3mg91uceg5/public_html/wp-content/plugins/learnpress/templates/single-course/content-item/popup-header.php
on line
22″

Can you help?

Thanks!