dbf_calculated_fee filter hook didn’t seem to work

On the checkout page, I added a select box with a list of regions for user to choose from.
On change, it updates the CheckoutURL with a parameter CHECKOUTURL?location=x_region, then in my theme’s functions.php I added the below line of code.

function my_dbf_calculated_fee_callback( $calculatedFee, $kiloMeters, $divider, $price ) {
    $customer_location =  $_GET['location'] ?? null;
    
    if($customer_location == 'x' || $customer_location == 'y') {
        $calculatedFee = 0;
    }
    return $calculatedFee;
}
add_filter( 'dbf_calculated_fee', 'my_dbf_calculated_fee_callback', 10, 4 );

To my surprise, when I choose x or y on the checkout page and it reloads the page, The distance based fee is not showing 0.

But when I echo the $calculatedFee above it returns 0, but the price on the checkout still remains unchanged.

Am I doing something wrong?

• This topic was modified 4 years, 9 months ago by solamichealolawale.

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