I am getting the same issue. Please advise me on how to fix it.

2021-03-08T13:02:44+00:00 CRITICAL Uncaught Error: Call to a member function get_cart() on null in /home/5/a/athletic1080/www/wp-content/themes/enfold-new/config-woocommerce/config.php:1800
Stack trace:
#0 /home/5/a/athletic1080/www/wp-includes/class-wp-hook.php(287): avia_woocommerce_cart_pos(Array, Array, ‘html_’)
#1 /home/5/a/athletic1080/www/wp-includes/plugin.php(212): WP_Hook->apply_filters(Array, Array)
#2 /home/5/a/athletic1080/www/wp-content/themes/enfold-new/functions-enfold.php(1138): apply_filters(‘avf_header_clas…’, Array, Array, ‘html_’)
#3 /home/5/a/athletic1080/www/wp-content/themes/enfold-new-child/header.php(12): avia_header_class_string()
#4 /home/5/a/athletic1080/www/wp-includes/template.php(730): require_once(‘/home/5/a/athle…’)
#5 /home/5/a/athletic1080/www/wp-includes/template.php(676): load_template(‘/home/5/a/athle…’, true, Array)
#6 /home/5/a/athletic1080/www/wp-includes/general-template.php(48): locate_template(Array, true, true, Array)
#7 /home/5/a/athletic1080/www/wp-content/themes/enfold-new/404.php(9): get_ in /home/5/a/athletic1080/www/wp-content/themes/enfold-new/config-woocommerce/config.php on line 1800