Woocommerce Phone Field İnput Mask - wordpress

Question

The code below works fine, but I want no special characters to be entered including the period. In addition, the phone number like "534-055-7888", which it masks, is also shown on the admin panel in the same way. I want it to show as "5340557888" without "-" in admin panel but I couldn't.
`
add_filter( 'woocommerce_checkout_fields', 'bbloomer_checkout_phone_us_format' );
function bbloomer_checkout_phone_us_format( $fields ) {
$fields['billing']['billing_phone']['placeholder'] = '123-456-7890';
$fields['billing']['billing_phone']['maxlength'] = 12; // 123-456-7890 is 12 chars long
return $fields;
}
add_action( 'woocommerce_after_checkout_form', 'bbloomer_phone_mask_us' );
function bbloomer_phone_mask_us() {
wc_enqueue_js( "
$('#billing_phone')
.keydown(function(e) {
var key = e.which || e.charCode || e.keyCode || 0;
var phone = $(this);
if (key !== 8 && key !== 9) {
if (phone.val().length === 3) {
phone.val(phone.val() + '-'); // add dash after char #3
}
if (phone.val().length === 7) {
phone.val(phone.val() + '-'); // add dash after char #7
}
}
return (key == 8 ||
key == 9 ||
key == 46 ||
(key >= 48 && key <= 57) ||
(key >= 96 && key <= 105));
});
" );
}
`