$pg_merchant_id = {{paybox_merchant_id}};
$secret_key = {{paybox_merchant_secret}};

$request = [
    'pg_merchant_id'=> $pg_merchant_id,
    'pg_order_id' => 1234,
    'pg_amount' => 100,
    'pg_user_id' => 12341,
    'pg_description' => 'Описание платежа',
    'pg_pan' => 4405645000006150,
    'pg_cvc' => 653,
    'pg_year' => 25,
    'pg_month' => 09,
    'pg_payment_to' => 4405645000006150,
    'pg_from_name' => 'Testov test',
    'pg_post_link' => 'http://site.kz/post',
    'pg_salt' => 'some random string',
];

//generate a signature and add it to the array
ksort($request); //sort alphabetically
array_unshift($request, 'p2p');
array_push($request, $secret_key); 

$request['pg_sig'] = md5(implode(';', $request)); // signature

unset($request[0], $request[1]);

$pg_merchant_id = {{paybox_merchant_id}};
$secret_key = {{paybox_merchant_secret}};

$request = [
    'pg_merchant_id'=> $pg_merchant_id,
    'pg_payment_id' => 1234,
    'pg_md' => '',
    'pg_pares' => '',
    'pg_salt' => 'some random string',
];

//generate a signature and add it to the array
ksort($request); //sort alphabetically
array_unshift($request, 'p2p_secure');
array_push($request, $secret_key); 

$request['pg_sig'] = md5(implode(';', $request)); // signature

unset($request[0], $request[1]);