Checkout customization

Hello!
I want to customize checkout page – disable some fields.
First of all i set they not required.

add_filter( 'woocommerce_billing_fields', 'altecs_address_field_optional');
    function altecs_address_field_optional( $fields ) {
    $fields['billing']['billing_postcode']['required'] = false; 
    $fields['shipping']['shipping_postcode']['required'] = false; 

    $fields['billing']['billing_address_1']['required'] = false; 
    $fields['shipping']['shipping_address_1']['required'] = false;
    return $fields; 
}

this code doesn’t work. i try another

function custom_my_fields($fields) {   
    $fields['billing']['billing_postcode']['required'] = false; 
    $fields['shipping']['shipping_postcode']['required'] = false; 

    $fields['billing']['billing_address_1']['required'] = false; 
    $fields['shipping']['shipping_address_1']['required'] = false;

     return $fields; 
}
add_filter("woocommerce_checkout_fields", "custom_my_fields");

this code doesn’t work too.

Can anybody helps – how to remove fields?

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