error upon pos checkout

hello,

When I proceed checkout and generate receipt in WooCommerce POS plugin, it shows the error code:

Fatal error: Uncaught Error: Call to a member function is_block_editor() on null in /home/customer/www/offtocook.com/public_html/wp-content/plugins/ultimate-member/includes/admin/core/class-admin-enqueue.php:660 Stack trace: #0 /home/customer/www/offtocook.com/public_html/wp-includes/class-wp-hook.php(307): um\admin\core\Admin_Enqueue->admin_enqueue_scripts('') #1 /home/customer/www/offtocook.com/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters(NULL, Array) #2 /home/customer/www/offtocook.com/public_html/wp-includes/plugin.php(476): WP_Hook->do_action(Array) #3 /home/customer/www/offtocook.com/public_html/wp-content/plugins/woocommerce-point-of-sale/includes/views/html-print-receipt.php(779): do_action('admin_enqueue_s...') #4 /home/customer/www/offtocook.com/public_html/wp-content/plugins/woocommerce-point-of-sale/includes/class-wc-pos.php(931): include_once('/home/customer/...') #5 /home/customer/www/offtocook.com/public_html/wp-includes/class-wp-hook.php(307): WC_POS->print_report('') #6 /home/cus in /home/customer/www/offtocook.com/public_html/wp-content/plugins/ultimate-member/includes/admin/core/class-admin-enqueue.php on line 660
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I can print the receipt in view order page but each print included an error receipt. Please help.

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