Hide Coupon Field on Cart and Checkout

<?php
if ( ! class_exists( 'WooCommerce' ) ) {
    return;
}

// Hide the coupon form on the cart page.
add_filter( 'woocommerce_cart_show_coupon', '__return_false' );

// Hide the coupon toggle link on the checkout page.
add_filter( 'woocommerce_checkout_show_terms', '__return_true' ); // unrelated, keep terms

add_filter( 'woocommerce_checkout_coupon_message', '__return_empty_string' );

// Remove the cart coupon action entirely.
add_action( 'woocommerce_cart_coupon', 'scseed_remove_cart_coupon_form', 0 );
function scseed_remove_cart_coupon_form() {
    remove_action( 'woocommerce_cart_coupon', 'woocommerce_cart_coupon' );
}