How do I send a http post request with an array as a post parameter in laravel

I am trying to send a post request in laravel. Below is my code:

$response = Http::withToken($local_signature)
    ->post('myUrl', [
        "amount" => $amount,
        "narration" => $narration,
        "currency" => $currency,
        "beneficiary_name" => $beneficiary_name,
        "reference" => $reference,
        "debit_currency" => $debit_currency,
        "callback_url" => $callback_url,

        "meta" => array(

            "account_number" => $account_number,
            "routing_number" => $routing_number,
            "swift_code" => $swift_code,
            "bank_name" => $bank_name,
            "beneficiary_name" => $beneficiary_name,
            "beneficiary_address" => $beneficiary_address,
            "beneficiary_country" => $beneficiary_country,

        )
    ]);

For some reason meta is not seen by the server as I keep getting error "meta is required and it must be a non-empty array". How do I send this post request with meta as an array?

I need the request to look like this:

{
  "amount": 500,
  "narration": "Sample USD Transfer",
  "currency": "USD",
  "beneficiary_name": "Mark Cuban",
  "meta": [
    {
     "account_number": "09182972BH",
     "routing_number": "0000000002993",
     "swift_code": "ABJG190",
     "bank_name": "BANK OF AMERICA, N.A., SAN FRANCISCO, CA",
     "beneficiary_name": "Mark Cuban",
     "beneficiary_address": "San Francisco, 4 Newton",
     "beneficiary_country": "US"
    }
  ]
}

Any help?

To have the same structure as that json, meta should be an array of arrays.

$response = Http::withToken($local_signature)
    ->post('myUrl', [
        'amount' => $amount,
        'narration' => $narration,
        'currency' => $currency,
        'beneficiary_name' => $beneficiary_name,
        'reference' => $reference,
        'debit_currency' => $debit_currency,
        'callback_url' => $callback_url,
        'meta' => [
            [
                'account_number' => $account_number,
                'routing_number' => $routing_number,
                'swift_code' => $swift_code,
                'bank_name' => $bank_name,
                'beneficiary_name' => $beneficiary_name,
                'beneficiary_address' => $beneficiary_address,
                'beneficiary_country' => $beneficiary_country,
            ],
        ],
    ]);