CM Pop-Up plugin causes fatal error

CM Pop-Up Banners causes a fatal error on the site. I’ve tried it on the production and staging sites. The free version seems to be the only plugin that will do what we need. Below is the warning. Thanks for any help!

WordPress version 6.7.2
Active theme: Hestia (version 3.2.8)
Current plugin: CM Pop-Up Banners for WordPress (version 1.7.7)
PHP version 8.1.31

Error Details
=============
An error of type E_ERROR was caused in line 19 of the file /var/web/staging/public_html/wp-content/plugins/cm-pop-up-banners/libs/wpalchemy/metaboxes/cm-help-items.php. Error message: Uncaught Error: Call to undefined function get_current_user() in /var/web/staging/public_html/wp-content/plugins/cm-pop-up-banners/libs/wpalchemy/metaboxes/cm-help-items.php:19
Stack trace:
#0 /var/web/staging/public_html/wp-content/plugins/cm-pop-up-banners/libs/wpalchemy/class/metabox.php(790): include()
#1 /var/web/staging/public_html/wp-admin/includes/template.php(1456): WPAlchemy_MetaBox->_setup(Object(WP_Post), Array)
#2 /var/web/staging/public_html/wp-admin/edit-form-advanced.php(722): do_meta_boxes(Object(WP_Screen), ‘normal’, Object(WP_Post))
#3 /var/web/staging/public_html/wp-admin/post-new.php(75): require(‘/var/web/stagin…’)
#4 {main}
  thrown

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