PHP - No me trabaja el $_POST en el cURL

curl_setopt($ch, CURLOPT_URL, "https://marketplace.api.healthcare.gov/api/v1/versions?apikey=xxxxxxxxxxxxxxxxxxxxx");

curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

curl_setopt($ch, CURLOPT_HEADER, FALSE);

curl_setopt($ch, CURLOPT_HTTPHEADER, array(

  "Accept: application/json"

));

$response = curl_exec($ch);

curl_close($ch);

var_dump($response);

string(523) "[{"name":"drugs","updated":"2020-06-16T14:10:13Z"},{"name":"npis","updated":"2020-10-13T17:41:51Z"},{"name":"issuers","updated":"2020-09-14T00:11:10Z"},{"name":"pet-seed","updated":"2017-05-23T00:00:00Z"},{"name":"zipcodes","updated":"2020-09-14T00:00:00Z"},{"name":"etl-id","updated":"20200916-210245"},{"name":"coverage","updated":"2020-10-19T19:38:29Z"},{"name":"plan-etl","updated":"2020-09-16T21:13:18.676046Z"},{"name":"plans","updated":"2020-09-14T12:57:58Z"},{"name":"taxonomies","updated":"2019-10-09T16:17:05Z"}] "

$ch = curl_init();

$datos = [

	"household" => [

		"income" => 52000,

		"people" => [

			[

				"age" => 27,

				"aptc_eligible" => true,

				"gender" => "Female",

				"uses_tobacco" => false

			]

		],

	],

	"market" => "Individual",

	"place" => [

		"countyfips" => "37057",

		"state" => "NC",

		"zipcode" => "27360"

	],

	"year" => 2020

];

$postdata = json_encode(array('data'=> $datos));

curl_setopt($ch, CURLOPT_URL, "https://marketplace.api.healthcare.gov/api/v1/versions?apikey=xxxxxxxxxxxxxxxxxx");

curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);

curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

curl_setopt($ch, CURLOPT_HEADER, FALSE);

curl_setopt($ch, CURLOPT_HTTPHEADER, array(

  "Accept: application/json"

));

$response = curl_exec($ch);

curl_close($ch);

var_dump($response);

string(0) ""

curl_setopt($ch, CURLOPT_POST, 1);

curl_setopt($ch, CURLOPT_VERBOSE, true);

string(0) ""