将变量传递给CURLOPT_URL时，Curl会返回错误的结果

I have a clue on my curl request, when i'm passing a variable to the CURLOPT_URL parameter i get bad values from response, when i hardcode the url curl returns good values :

class APi {
   public $this->url;
   public $this->token; // :)
   function __construct($url, $token){
       $this->url = $url;
       $this->token = $token;
   }

function getUsers(){
    $curl = curl_init();
    curl_setopt_array($curl, array(
    CURLOPT_PORT => "4000",
    CURLOPT_URL => $this->url,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_ENCODING => "",
    CURLOPT_MAXREDIRS => 10,
    CURLOPT_TIMEOUT => 30,
    CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
    CURLOPT_CUSTOMREQUEST => "GET",
    CURLOPT_HTTPHEADER => array(
        "Cache-Control: no-cache",
        "Content-Type: application/x-www-form-urlencoded",
        "Postman-Token: 472244a4-af1d-4ca5-b26b-07f6b168c04b",
        "x-access-token:" . $this->token
    ),));

    $response = curl_exec($curl);
    $err = curl_error($curl);

    curl_close($curl);

    if ($err) {
        echo "cURL Error #:" . $err;
    } else {
        print_r($response); //<== print bad values when CURLOPT_URL value is a variable
        return $response;
    }
  }
} // end of class api

// Init the class
$data = new Api($url, $token);
print_r($data->getUsers());

the $this->url is initialised from the constructor, when i paste the value of $this->url to postman i get good results but from code i get bad results.

Someone can helps me ?

thank you.

====== SOLUTION ==========

From advices of some of you i have to urlencode individual parameter value, and it works as excepted. Thanks for the var_dump tip to compare characters length.