Why does the bool(FALSE) JSON error occur?

Question

PHP

I'm trying to learn how to work with JSON, but I don't understand why an error occurs ... Here's the cad:

$jsonString = '
{
  "payment_type": 1,
  "address": {
      "town_id": 1,
      "street": "Яузская аллея",
      "house_number": "2",
      "underground": null,
      "comment": "Яузская аллея, д. 21А",
      "house_frame": "",
      "flat_number": "",
      "house_building": ""
  }
}                               
';
$cart = json_encode($jsonString, TRUE);
print $cart->payment_type;
print var_dump($cart);

bool(false) - request error...
What's wrong? :)

Answer 1

json_encode($jsonString, TRUE);
Well, you decode into an array, but you access it as an object

Answer 2

print $cart['payment_type'];
And not town, but city.

Answer 3

Thanks to everyone for the answers :) Everything is much simpler :))))))
There was a different encoding!