paypal-error

//GetAccessToken
        $tHead = array("Accept: application/json","Accept: application/x-www-form-urlencoded","Accept-language: hu_HU");
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_URL, "https://api.sandbox.paypal.com/v1/oauth2/token");
        curl_setopt($ch, CURLOPT_HTTPHEADER, $tHead);
        curl_setopt($ch, CURLOPT_USERPWD, "".$this->clientID.":".$this->secretKey."");
        curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, "grant_type=client_credentials");
        $result = curl_exec($ch);
        $result = json_decode($result,true);
        $token = $result['access_token'];
        curl_close($ch);

        //Create order
        $json = '{"intent":"CAPTURE","purchase_units":[{"reference_id":"2019/t001","amount":{"currency_code":"USD","value":"1.00"}}]}';
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_URL, $this->apiUri);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: application/json", "Authorization: Bearer ".$token.""));
        curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $json);
        $result = curl_exec($ch);
        $result = json_decode($result,true);
        curl_close($ch);

        //Show order details
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_URL, "https://api.sandbox.paypal.com/v2/checkout/orders/".$result['id']);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: application/json", "Authorization: Bearer ".$token.""));
        $result = curl_exec($ch);
        $result = json_decode($result, true);
        curl_close($ch);
        echo("<script>window.open('".$result['links'][1]['href']."','pay','width=500,height=500');</script>");

        //DebugOutput
        print_r($result);