PHP read HTTP/2 response Body

Question

I want to read HTTP/2 response in php.

Below is the code I have.

     $ch = curl_init();
        curl_setopt_array($ch, [
        CURLOPT_URL            =>$url,
        CURLOPT_HEADER         =>1,
        CURLOPT_CUSTOMREQUEST  =>'GET',
        CURLOPT_RETURNTRANSFER =>true,
        CURLOPT_HTTP_VERSION   =>CURL_HTTP_VERSION_2_0,
        CURLOPT_HTTPHEADER     =>$headers,
        CURLOPT_PROXY          =>$proxy,
        CURLOPT_SSL_VERIFYPEER =>False,
        CURLOPT_COOKIE         =>$sessionCookie,
        CURLOPT_VERBOSE         =>0,
    ]);
    $response = curl_exec($ch);
    $curl_info = curl_getinfo($ch);
    curl_close($ch);

    $header_size = $curl_info['header_size'];
    $download_content_length = $curl_info['size_download'];
    
    $headers = substr($response, 0, $header_size);
    $body = substr($response, $header_size, $download_content_length);
    $jsondata = json_decode($body,TRUE);

Notice that when I send the request through Proxy(Burp,ZAP) I am able to read the response. But, when I disable the proxy. I am unable to read the response body.

Below is the error I get:

Exception: Trying to access array offset on value of type null in test.php:77

where Line 77 is the last line from the above code.

Below is the var_dump of the $response:

HTTP/2 200
date: Mon, 21 Jun 2021 15:38:44 GMT
content-type: application/json; charset=utf-8
content-length: 788
content-encoding: gzip
x-frame-options: SAMEORIGIN
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
strict-transport-security: max-age=15552000; includeSubDomains; preload
referrer-policy: origin
permissions-policy: geolocation=(self), microphone=(), camera=()
content-security-policy: default-src 'self' 'unsafe-inline' 'unsafe-eval' wss: https:; img-src 'self' data: https:; style-src 'self' 'unsafe-inline' https:;

���Ooƿ
�¼�3��zʩ�)����Ĩj����\r-K#��3��C�G�pz8�=�|<-�r~��?��eW>���O�e�������>����Z�����P��?��2����l��h�*&�G�
a�*fVˮ�;��n@5tea�

It is in unreadable format. How can i read them?