Only reduce stock inventory on completed orders in WooCommerce

functions.php

add_action( 'init', 'custom_wc_maybe_reduce_stock_levels', 10 );
function custom_wc_maybe_reduce_stock_levels(){
    // remove_action( 'woocommerce_order_status_completed', 'wc_maybe_reduce_stock_levels' );

    remove_action( 'woocommerce_payment_complete', 'wc_maybe_reduce_stock_levels' );
    remove_action( 'woocommerce_order_status_processing', 'wc_maybe_reduce_stock_levels' );
    remove_action( 'woocommerce_order_status_on-hold', 'wc_maybe_reduce_stock_levels' );
    
    add_action( 'woocommerce_payment_complete', 'wc_maybe_increase_stock_levels' );
    add_action( 'woocommerce_order_status_processing', 'wc_maybe_increase_stock_levels' );
    add_action( 'woocommerce_order_status_on-hold', 'wc_maybe_increase_stock_levels' );
}

https://stackoverflow.com/questions/76321233/allowing-inventory-stock-count-reduction-only-for-completed-orders-in-woocommerc/76321869