Wp error

Getting this error over the last few days. And as your mentioned from #5 thought I should find out more.

Détails de l’erreur======================Une erreur de type E_ERROR a été causée dans la ligne 91 du fichier /home///wp-content/themes/spacious/inc/header-functions.php. Message d’erreur : Uncaught Error: Call to a member function get_cart_contents_count() on null in /home///wp-content/themes/spacious/inc/header-functions.php:91Stack trace:#0 /home///wp-content/themes/spacious-child/header.php(154): spacious_cart_icon()

#1 /home///wp-includes/template.php(783): require_once(‘/home///…’)#2 /home///wp-includes/template.php(718): load_template(‘/home///…’, true, Array)

#3 /home///wp-includes/general-template.php(48): locate_template(Array, true, true, Array)

#4 /home///wp-content/themes/spacious/404.php(9): get_header()

#5 /home///wp-content/plugins/wp-cerber/cerber-load.php(4662): include(‘/home//…’)

#6 /home///wp-content/plugins/wp-cerber/cerber-load.php(2453): cerber_404_page()

#7 /home///wp-content/plugins/wp-cerber/cerber-load.php(2

Regards