Guzzle POST error response: {"error":"Item data is missing"}

Hi,

I am recently trying to post new record into collection with http guzzle

The call looks like this. Instead of whatever is _id of record

$page = $this->client->request('POST', $this->api . '/content/item/elearning', [
            'query' => [ 'api-key' => $this->token],
            'body' => json_encode(["data" => [
                "_id" => "whatever"
            ]]),
        ]);

In result I get Guzzle POST error response: {"error":"Item data is missing"} 

Did any of You got the same problem?

Can you try to add this additional headers option to the request?

'headers' => [
  'Content-Type' => 'application/json',
]