Access protected data response by UPS address validiator

I am using gabrielbull/ups-api for validating user address if a user provides an address I verify weather the address is correct or not I am using a got and getting a response which is quite difficult for me to access the data here is what I am getting in return

Ups\Entity\AddressValidationResponse Object
(
    [response:protected] => SimpleXMLElement Object
        (
            [ValidAddressIndicator] => SimpleXMLElement Object
                (
                )

            [AddressKeyFormat] => SimpleXMLElement Object
                (
                    [AddressLine] => 2290 SW 128TH AVE
                    [Region] => MIRAMAR FL 33027-2648
                    [PoliticalDivision2] => MIRAMAR
                    [PoliticalDivision1] => FL
                    [PostcodePrimaryLow] => 33027
                    [PostcodeExtendedLow] => 2648
                    [CountryCode] => US
                )

        )

    [requestAction:protected] => 1
)

This is the code I used

$address = new \Ups\Entity\Address();
$address->setAddressLine1('2290 SW 128th Street');
$address->setAddressLine2('');
$address->setStateProvinceCode('FL');
$address->setCity('Miramar');
$address->setCountryCode('US');
$address->setPostalCode('33027');

$eyaccessKey = 'key';
$userId = 'user id';
$password = 'password';
$xav = new \Ups\AddressValidation($accessKey, $userId, $password);
$xav->activateReturnObjectOnValidate(); //This is optional

try {
    $response = $xav->validate($address);

    echo "<pre>";
    print_r($response);
    echo "</pre>";
} catch (Exception $e) {
    var_dump($e);
}

I tried to access the data by accessing the data using json object but I am unable to access there is what I tried to do

$response->response()->AddressKeyFormat

But I was unsuccessful I am not pretty much sure how do I access this data can anyone help me out hwo do validate address .