Why am I getting different curl results when using CLI vs php?

I have a simple curl statement to igdb.com

curl 'https://api-v3.igdb.com/games/?search=atari%20flashback&fields=cover,name' -H 'user-key: KEYKEY' -H 'Accept: application/json'

When I run that I get a list of items with the id, cover, and name (as requested with the fields field). To be able to use it on my site I use the following php_curl code.

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://api-v3.igdb.com/games/");
    curl_setopt($ch, CURLOPT_POST, 1);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array(
        "Accept: application/json",
        "user-key: KEYKEY",
    ));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);

    $postData = array(
        'search' => 'atari flashback',
        'fields' => 'cover,name'
    );

    curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
    $response = curl_exec($ch);
    curl_close($ch);

But with that code I only get the ids, like the fields field is being ignored. What am I doing wrong here?