currency error

<?php
// include stripe PHP lib path here

// set up API key
\Stripe\Stripe::setApiKey("your API key here");

$managed_account = \Stripe\Account::create([
    'managed' => true,
    'email' => '[email protected]'
]);

// create a debit card recipient
$token = \Stripe\Token::create([
    'card' =>[
          'name' => 'John Doe',
          'number' => '4000056655665556',
          'exp_month' => '01',
          'exp_year' => '2020',
          'cvc' => '123',
          'address_line1' => '1207 2nd St',
          'address_line2' => '2rd Floor',
          'address_state' => 'CA',
          'address_city' => 'Santa Monica',
          'address_zip' => 90401,
//          'currency' => 'usd'
    ]
]);
$recipient = \Stripe\Recipient::create([
    "name" => 'John Doe',
    "type" => "individual",
    'card' => $token->id
]);
       
// re-tokenize the debit card recipient
$token = \Stripe\Token::create(
    [
        'recipient' => $recipient->id,
        'card' => $recipient->cards->data[0]->id
    ],
    [
        'stripe_account' => $managed_account->id
    ]
);

// link the debit card to the managed account
$managed_account->external_accounts->create([
    'external_account' => $token->id
]);
$managed_account->save();

I have tried to assign the currency to the card like this after line 26, but it didn't help:

        $recipient->cards->data[0]->currency = 'usd';
        $recipient->save();