Woocommerce - validate coupon with cart items & coupon data - function

Question

I’m in the process of validating a coupon on cart items rather than the order as a whole. If the cart items exceeds the number of available coupon limit, the coupon errors and gives the user an error message.
The code below checks how many specific product items are in the basket, for example 5. // This works
The code below also returns data from the coupon being used. // This doesn’t work
Example of the data im looking to return so I can compare.
coupon code = 123
coupon usage_count = 1
coupon usage_limit = 3
Available usage = 2
I already have another coupon validation in place that checks whether a users facilities booking falls in between their hotel booking dates, that works fine. Anyone have any suggestions where I’m going wrong with this validation? I can’t seem to return the data from the coupon being inputted. Am I using the correct filter? Thanks
add_filter( 'woocommerce_coupon_is_valid', 'coupon_validation_quantity', 10, 2);
function coupon_validation_quantity($valid, $coupon) {
global $wpdb;
global $woocommerce;
global $product_items_in_cart;
$product_id = 493;
$product_items_in_cart = 0;
foreach ( WC()->cart->get_cart() as $cart_item ) {
$cart_product_id = $cart_item['product_id'];
if($cart_product_id == $product_id){
$product_items_in_cart++;
};
};
global $product_items_in_cart;
global $cart_coupon_code;
global $cart_coupon_count;
global $cart_coupon_limit;
global $cart_coupon_available;
$applied_coupons_code = WC()->cart->get_applied_coupons();
$coupon_in_cart = new WC_Coupon($applied_coupons_code);
$cart_coupon_code = $coupon_in_cart->get_code();
$cart_coupon_count = $coupon_in_cart->get_usage_count();
$cart_coupon_limit = $coupon_in_cart->get_usage_limit();
$cart_coupon_available = ($cart_coupon_limit - $cart_coupon_count);
print_r('products in cart -> ' . $product_items_in_cart . "\r\n"); // return correct
print_r('available -> ' . $cart_coupon_available . "\r\n"); // returns zero
if($product_items_in_cart > $cart_coupon_available){
$valid = false;
};
return $valid;
}
Coupon Error Handling
add_filter( 'woocommerce_coupon_error', 'coupon_validation_error_quantity', 10, 3);
function coupon_validation_error_quantity($err, $err_code, $coupon) {
global $wpdb;
global $woocommerce;
global $product_items_in_cart;
global $cart_coupon_available;
print_r('products in cart -> ' . $product_items_in_cart . "\r\n"); // returns correctly
print_r('available -> ' . $cart_coupon_available . "\r\n"); // returns Zero
if($product_items_in_cart > $cart_coupon_available && intval($err_code) === WC_COUPON::E_WC_COUPON_INVALID_FILTERED){
$err = __( "Coupon $cart_coupon_code exceeds available usage. You have $cart_coupon_available available ", "woocommerce" );
};
return $err;
}